hello friends,
maybe someone of you is able to help, or at least enlighten me about the cause of this:
since i use ICS on my note (about for 2 weeks, starting with stunner) i have REALLY BIG problems with one of my exchange accounts, the one which is running on a hosted exchange 2007 (second account with my corporate exchange 2010 is fine)! so until today i hoped that the "official ICS" for the note won't show this behavior, but now with a total clean install of the today released LPY and therefore OFFICIAL SAMSUNG ICS rom, the problem persists!
description:
95 out of 100 trys to connect to my exchange account fails with a message telling me that there is a security error (if needed i can provide some screenshots) telling me that either my username and/or password is incorrect! this makes it almost impossible even to simply add the account. and, on the rare occasions (which SOMETIMES can be triggered through a connection change between wifi and 3g) when the phone is able to connect (and sync), it stops after a few minutes again with the same error.
i re-added the account numerous times, tried everything which came through my mind (change password, enabled and disabled sec features) and trust me, i know what i'm doing here. i configure exchange accounts since almost 10 years from now!
clues:
there are a few tickets existing on http://code.google.com/p/android regarding this issue, but with different "flavours":
http://code.google.com/p/android/issues/detail?id=16992
http://code.google.com/p/android/issues/detail?id=19366
http://code.google.com/p/android/issues/detail?id=25315
to sum it up:
google developers are recognizing the problem (it seems to exist since android 3+ to some extent) but are unable to provide a solution until now. it seems to be a problem with an EAS policy refresh, which fails and therefore closes (or does not even open) the connection! a guy suggested to disable these policy refresh in the EX2007 config, but this would only be possible if you are the admin of this server (and i doubt that it would make sense, security-wise, too)!
another theory says this mess is due to implementation errors in the connection layer, which directly affects wifi and 3g connection behavior...
i guess that this problem would now get's more imminent, as this security error wasn't occurring at gingerbread. and now more and more people with smartphones will migrate to ICS!
what do you think?
does anybody else experience this? or am i one of the few unlucky bastards?
regards,
markus
so, is exchange 2007 working for everyone?
this would be important to know for me, because in this case i would have
to blame my exchange provider for wrong EAS settings!
can a few people with an exchange 2007 account confirm that their sync work flawlessly? anyone please?
Just realized my exchange account is not syncing unless I open the client.
My work is running exchange 2003
Never had this issue with imilka ROM weird
Sent from my GT-N7000 using xda premium
mardos said:
Just realized my exchange account is not syncing unless I open the client.
My work is running exchange 2003
Never had this issue with imilka ROM weird
Sent from my GT-N7000 using xda premium
Click to expand...
Click to collapse
This seems to be the case on all TW based roms, no matter if GB or ICS at least for me. It syncs fine with Hotmail service but not with my company's 2003 server so there has to be some incompatibility there. When disabling all syncs and re-enabling them it started syncing. Just had to wait for about 30 minutes to get all info synced.
E: On AOSP based (CM9, AOKP) everything works as it should right from the beginning without the extra hassle.
I'm working properly in Galaxy Note, from KKA to LPY, with Exchange 2007 SP3.
Syncing is correct in my case.
Samsungs version of ICS (or Gingerbread) doesn't communicate with Lotus Notes traveler active sync. Cyanogen 9 (ICS) is working out of the box. In Gingerbread the Traveler App is working but in Samsungs version of ICS the widgets dont work.
after fiddling around this WE i think there would be no other solution as reverting back to GB (which would suck, and therefore is no real option), or to change to a hoster with exchange 2010!
every client i tried shows the same behavior, if i'm able to establish a connection it won't last long till the security error reappears! this renders my account almost useless...
i will update this post if something changes!
Related
Hi there -
I work under contract for my job. At the end of the year, they generally axe all of us, and bring me back. Since I'm a domain admin, they generally strip my rights and disable my account. This time, when I was brought back - I couldn't use my email on my phone (CM 6.1) using either Touchdown or the Email client. I changed my password and everything. I've since installed CM 7 Nightly build 18, and it's still the same. The problem is it says: "Authentication Failed." When I log into my exchange server I'm enabled for Active Sync and OWA. And I've been back for three weeks.
I'm wondering if this is a potential problem with Android 2.2+? I'm going to reformat my SD card in case it has bad SSL certs saved for the app.
Any ideas would be great
Sent from my HTC Vision using XDA App
Hi,
I have heard, heard only mind, that exchange can have issues with HTC devices if you do NOT have an HSDCS (HSD, High Speed Data etc)connection and thus you get sync errors.
Never had a problem on my desire with stock 1.72 (damn and double damn as I don't have root as yet!) and exchange. Bar those few occasions I was actually outside a reception area.
Certificates shouldn't cause an authentication issue unless personal ones, no? Sounds odd.
Des. . .
hello,
i am so chocked that nobody is complaining about Exchange security not working with GRI40 either. the only ROM working fine are HTC Sense rom...
i know it is not important for most of you but i am stucked with a phone that cannot connect to my Exchange system...but i want vanilla ROM working...
I have no issues.
securities policy
difrnt said:
I have no issues.
Click to expand...
Click to collapse
Password/PIN required
failed attempts 10
Min Length 5
Timeout 1800 sec.
Password recovery.
This is what i need and this is not supported by vanilla Android ROM.
Only touchdown and HTC sense support this.
So this work for you but only for basic security, not like 95 % of enterprise companies out there...
Best
cedricj said:
Password/PIN required
failed attempts 10
Min Length 5
Timeout 1800 sec.
Password recovery.
This is what i need and this is not supported by vanilla Android ROM.
Only touchdown and HTC sense support this.
So this work for you but only for basic security, not like 95 % of enterprise companies out there...
Best
Click to expand...
Click to collapse
Maybe only 5% of the companies have that restriction??
I have used my phone with two different "enterprise" companies and have not had an issue.
No issues here either. Using a major law firms exchange.
Liking the update to include signatures on replies now. That's the way it should be.
Exchange Sync Issues
I also had (have?) issues and I mentioned them as part of another note on my overall response to 2.3.3. (in a phrase, not worth it) but nobody else seemed to be interested in that thread. So, welcome.
2.3.3. on my stock N1 has suffered the following problems:
1. Would not connect to Exchange server after I updated to 2.3.3
2. So I cleared data in "email" app, forced close, and tried to reinstall from
Home>Menu>Accounts. Also rebooted.
3. When trying to install from Home>Menu>Accounts I found NO PROVISION FOR MANUAL SETUP, i.e., manually entering domain name and exchange server ID; you can only enter your email address and password. The Gingerbread Manual mentions there is provision for manual setup in case of problems, but they don't tell you that you have to. . .
4. Set up from eMail App in the App drawer. When I set up that way there is a button for Manual Install.
5. Without Manual Install it is probable that your phone is assuming a domain name or ID that is wrong, and it will never connect.
6. After the successful re-install and use for about a day, 2.3.3. wiped out my server connection again arbitrarily (I never turn the phone off/on, etc.; it just did it) and I had to set up again.
This is definitely a BUG in 2.3.3--very definitely the inability to manually set up from any screen on which you can set up an account.
Same problem here, although it looks that Exchange is setup correctly -following instructions of ecdy, there is NO data synchronization at all with my exchange account! As under Froyo there were no problems at all, this MUST be a Gingerbread bug. Anybody any solution, workaround, please?
N1, unrooted stock, 2.3.3. OTA.
ecdy said:
I also had (have?) issues and I mentioned them as part of another note on my overall response to 2.3.3. (in a phrase, not worth it) but nobody else seemed to be interested in that thread. So, welcome.
2.3.3. on my stock N1 has suffered the following problems:
1. Would not connect to Exchange server after I updated to 2.3.3
2. So I cleared data in "email" app, forced close, and tried to reinstall from
Home>Menu>Accounts. Also rebooted.
3. When trying to install from Home>Menu>Accounts I found NO PROVISION FOR MANUAL SETUP, i.e., manually entering domain name and exchange server ID; you can only enter your email address and password. The Gingerbread Manual mentions there is provision for manual setup in case of problems, but they don't tell you that you have to. . .
4. Set up from eMail App in the App drawer. When I set up that way there is a button for Manual Install.
5. Without Manual Install it is probable that your phone is assuming a domain name or ID that is wrong, and it will never connect.
6. After the successful re-install and use for about a day, 2.3.3. wiped out my server connection again arbitrarily (I never turn the phone off/on, etc.; it just did it) and I had to set up again.
This is definitely a BUG in 2.3.3--very definitely the inability to manually set up from any screen on which you can set up an account.
Click to expand...
Click to collapse
I do believe there is an issue with not having the manual setup option. I read somewhere on here that someone got the manual option after the automatic setup failed 10 times. A bug yes, but once account is set up, everything works as it should.
derfo said:
I do believe there is an issue with not having the manual setup option. I read somewhere on here that someone got the manual option after the automatic setup failed 10 times. A bug yes, but once account is set up, everything works as it should.
Click to expand...
Click to collapse
No, pity, NOTHING works as it should - read my post above, please. Since Gingerbread (N1, stock, unrooted, 2.3.3. OTA) exchange sync lost, although it LOOKS set up correctly (accepts all, password, username) does NOT sync mail, calendar!
Anybody any solution please?
Strange thing noticed: after OTA Gingerbread Hotmail account in mail survived, exchange account (company) went lost.. Anything to do with problem?
bmszabo said:
No, pity, NOTHING works as it should - read my post above, please. Since Gingerbread (N1, stock, unrooted, 2.3.3. OTA) exchange sync lost, although it LOOKS set up correctly (accepts all, password, username) does NOT sync mail, calendar!
Anybody any solution please?
Strange thing noticed: after OTA Gingerbread Hotmail account in mail survived, exchange account (company) went lost.. Anything to do with problem?
Click to expand...
Click to collapse
I did a manual upgrade to GB (clean upgrade). Maybe the OTA has broken something.
Exchange Sync problems
As far as other email accounts are concerned: GMail worked fine; Yahoo! Mail, which was originally set up in the OS's "Accounts" mode, didn't work. Downloading the Yahoo! Mail App fixed that.
Maybe there's a Hotmail app too.
It sounds like bmszabo isn't getting refreshed (synced); check all accounts settings that adjust sync frequency and do a "sync now" to see if it works.
Before I erased all the data in my Exchange a/c on the phone I would get a screen with all my emails and contacts up to the point where I had installed 2.3.3, but nothing thereafter. The phone will store old data but if it can't connect to the server it won't add anything new. Why does bmszabo say "it LOOKS set up correctly (accepts all, password, username)"? It will remember the correct pwd and username as you put them in, along with an incorrect domain name and server, and never be able to connect.
ecdy said:
It sounds like bmszabo isn't getting refreshed (synced); check all accounts settings that adjust sync frequency and do a "sync now" to see if it works.
Before I erased all the data in my Exchange a/c on the phone I would get a screen with all my emails and contacts up to the point where I had installed 2.3.3, but nothing thereafter. The phone will store old data but if it can't connect to the server it won't add anything new. Why does bmszabo say "it LOOKS set up correctly (accepts all, password, username)"? It will remember the correct pwd and username as you put them in, along with an incorrect domain name and server, and never be able to connect.
Click to expand...
Click to collapse
Sorry, trying to explain things happened since GB OTA upgrade: after setting up exchange account, Exchange sync setup looks allrite, after asking about administrator priorities (and accepting them) sync sign turns green, looks like account setup correct, shows empty mailbox, but it DOES NOT sync with my mail, neither with calendar; as a matter of fact, my exchange calendar does not even show up on the list of calendars in Agenda...
O yes, forgotten: manual sync, although green wheel spins shortly, does not change a thing, neither..
Another similar issue with Exchange not syncing came up with CM 6.1.1. The fix was to reinstall the Email.apk.
http://forum.cyanogenmod.com/topic/13900-fix-exchange-2010-activesync/
ecdy said:
3. When trying to install from Home>Menu>Accounts I found NO PROVISION FOR MANUAL SETUP, i.e., manually entering domain name and exchange server ID; you can only enter your email address and password. The Gingerbread Manual mentions there is provision for manual setup in case of problems, but they don't tell you that you have to. . .
Click to expand...
Click to collapse
Firstly, you enter email and password. If you want to include domain name - you write your email like this: domain\[email protected]
After you enter it, whether it fails or succeeds - it presents you with manual setup screen.
derfo said:
Maybe only 5% of the companies have that restriction??
I have used my phone with two different "enterprise" companies and have not had an issue.
Click to expand...
Click to collapse
5 % pf the companies uses Exchange security? you must be kidding right? what my company is asking for in term of security is just basic. So i cannot believe that sorry.
This is really basic functionalities for security. It works on iphone, on Sense, on Symbian, but not on Android. So i am not getting it. If it works everywhere else than Android, it means that definitively more than 5 % of companies are requiring these basic security features.
My 2 cents of course and nothing personal!
best
cedricj said:
5 % pf the companies uses Exchange security? you must be kidding right? what my company is asking for in term of security is just basic. So i cannot believe that sorry.
This is really basic functionalities for security. It works on iphone, on Sense, on Symbian, but not on Android. So i am not getting it. If it works everywhere else than Android, it means that definitively more than 5 % of companies are requiring these basic security features.
My 2 cents of course and nothing personal!
best
Click to expand...
Click to collapse
What I am saying is that there are plenty of people who are able to connect to their Exchange servers just fine which do HAVE exchange security enabled. Maybe your company has additional security restrictions enabled. If so, then your company will fall in the 5% subset.
derfo said:
What I am saying is that there are plenty of people who are able to connect to their Exchange servers just fine which do HAVE exchange security enabled. Maybe your company has additional security restrictions enabled. If so, then your company will fall in the 5% subset.
Click to expand...
Click to collapse
well got your point... But why does all vendors supports the ""Only"" 5 % but not Android?
well...
who cares... probably the answer...
Best
I am using cyanogenmod 7 RC1 (gingerbread) and have tried multiple roms including googles vanilla and NONE of them have supported my company's exchange setup. This was supposed to be fixed in froyo and for people using sense it is fixed.
Basically when i manually setup activesync it says the phone doesn't support the security features.
Who cares if my company uses extra security or not. It works on HTC and iphone/ipad.
Google is basically doing half assed exchange support and I will keep telling people they will probably need to shell out for touchdown if they move to android until they fix it.
Google needs to support ALL ACTIVESYNC SECURITY settings, anything less isn't good enough.
I think You are right; Exchange sync (cal, mail) worked PERFECT with Froyo, and with Gingerbread it is completely lost.. I don't think any firm can do this to customers using their OS, and I do hope somebody gots a solution soon (or: Google fixes the issue?).
In the meanwhile: as I cannot use my company mail/ calendar: I wish I stayed with Froyo!!
jerkfaceirl said:
I am using cyanogenmod 7 RC1 (gingerbread) and have tried multiple roms including googles vanilla and NONE of them have supported my company's exchange setup. This was supposed to be fixed in froyo and for people using sense it is fixed.
Basically when i manually setup activesync it says the phone doesn't support the security features.
Who cares if my company uses extra security or not. It works on HTC and iphone/ipad.
Google is basically doing half assed exchange support and I will keep telling people they will probably need to shell out for touchdown if they move to android until they fix it.
Google needs to support ALL ACTIVESYNC SECURITY settings, anything less isn't good enough.
Click to expand...
Click to collapse
Agree with you...
thank you for your support. Started to feel alone here!
Spotty with froyo. Now does not work at all.
Sent from my DROIDX using XDA App
Cant even do it with touchdown. Everything else works great.
Sent from my DROIDX using XDA App
I'm syncing with a hosted Exchange 2010 server (outlook.com). I had to change the server address from m.outlook.com to the actual pod*****.outlook.com address, but after that it's working perfectly with my DX on GB.
We have Exchange 2003. Tried everything.
I lose synch whenever my ROM changes.
The first time, I deleted my corp account, and recreated it...that worked.
The second time, I re-entered just my password and the last field had changed the name, not sure why...but fixed that and it resynched after both of those.
It stopped working for me too, but I haven't tried inputting the actual outlook exchange address. We always used m.mycompanyname.com.
Apparently Motorola knows about the problem. I just did a simple google search on my pop up about not being able to provision for my device. So much for "enhanced activesync" lol:
http://motorola-global-en-usa.custh...id-pro-after-mr2-update-(copy-of-answer-67174)
Still no corporate email or calendar sync. I've nuked phone clean and it still won't update.
Another e/ee here received the OTA update from Verizon and it ruined her corp sync too. So it has nothing to do with root.
I think there is some issue with pulling the certificate.
Corporate Email won't configure OTA GB 2.3
crawcraw said:
Still no corporate email or calendar sync. I've nuked phone clean and it still won't update.
Another e/ee here received the OTA update from Verizon and it ruined her corp sync too. So it has nothing to do with root.
I think there is some issue with pulling the certificate.
Click to expand...
Click to collapse
I think you are right about the issue having to do with pulling a certificate.
In my case, first OTA install failed, then Verizon folks had me flash back to 2.2, wiping my existing settings.
After the rollback, I was able to install the OTA to get to 2.3 successfully, but now I am not able to setup corporate sync on the phone. All correct settings gets me an error message saying "Login to the server failed, please try again."
One thing I notice is that on the 2.2 Corporate Sync settings, it asks for:
"domain/username" in one textbox
where on the 2.3 settings page, the username and domain are entered on separate textboxes.
Maybe that has nothing to do with anything, but it was something I noticed.
I'll update if I find anything about this issue.
****update
Call was disconnected with VZ, Moto, and I'm too mad/tired to go through the hassle again. Boo.
Droid X - Activesync issues after GB Update
So this is really strange, and I'm truly frustrated. The Mobile device policy in our Exchange 2007 environment will not allow the Corporate Mail application on our DXs provision with the server... unless we check the Allow Simple Passwords option in the policy itself. Then the device is provisioned properly and email, calendar and contacts sync.
This is not optimal as we have a strict Policy for passwords and using a simple password violates that.
Regards,
Edge
I feel your pain Edge... same for me.. doesn't allow for simple passwords. So now I am receiving the provisioning error. I called Verizon lastnight... they forwarded me to motorola and they said for me to send a document stating the settings my company needs to change.. what a joke. I am furious. I don't want third party software to download email... Although my HTC Eris sucked because of the speed.. the company HTC supported my email. Every time there was an upgrade it continued to work.
still busted. Tried several things with my company's outside tech support.
Exchange 2003. Factory reset of phone (twice). Even pulled the SD card after the second factory reset. I manually added certificates. Tried Touchdown. turned SSL on, turned off.
tried all kinds of domain settings. Tried stuff on server side. Still nothing.
Now I'm getting error messages with Gmail.
SUCCESS!
Our certificate expires in August so the IT guy went ahead and updated it. When turning on account, I left off the domain name and checked SSL. Worked immediately after that. Good luck.
FWIW, i just upgraded to p3droid's rooted GB (performed a full data reset in the process). Setting up my corporate sync was painless (worked first try) and it works flawlessly. Our IT guy is sharp and knows how to configure and maintain our Exchange server with all the latest updates and such. If anyone is having issues with Corporate Sync, I'll bet a dollar that it's a problem with your Exchange Server and not GB.
BBJohnnyT said:
FWIW, i just upgraded to p3droid's rooted GB (performed a full data reset in the process). Setting up my corporate sync was painless (worked first try) and it works flawlessly. Our IT guy is sharp and knows how to configure and maintain our Exchange server with all the latest updates and such. If anyone is having issues with Corporate Sync, I'll bet a dollar that it's a problem with your Exchange Server and not GB.
Click to expand...
Click to collapse
Exchange support on any android platform is usually from a mis-maintained Exchange server, but it just seems that motorola is extra messed up with their support. I know how my Exchange server is set up and I still have a hard time getting full functionality out of my DX and my corporate email account. At my work I depend on calender support because it's the main means of communication between our IT staff as to who is going to in the office at what point. As of right now, I'm using my work phone to keep up with work which is... Normal? I dunno, but I just know I'll have to float until I can get my hands on a decent root and ROM for the OTA update. I've tried using P3droid's patched version and out of the six times I've tried it, I've either gotten into a boot loop or I've lost all data connectivity- weird.
Laramie1997 said:
Exchange support on any android platform is usually from a mis-maintained Exchange server, but it just seems that motorola is extra messed up with their support. I know how my Exchange server is set up and I still have a hard time getting full functionality out of my DX and my corporate email account. At my work I depend on calender support because it's the main means of communication between our IT staff as to who is going to in the office at what point. As of right now, I'm using my work phone to keep up with work which is... Normal? I dunno, but I just know I'll have to float until I can get my hands on a decent root and ROM for the OTA update. I've tried using P3droid's patched version and out of the six times I've tried it, I've either gotten into a boot loop or I've lost all data connectivity- weird.
Click to expand...
Click to collapse
I had lots of weirdness with GB too when I upgraded (twice) using P3droid's update. I SBFed back to .340 and then did a Factory Data Reset just prior to booting into Clockworkmod's Recovery to do the upgrade. Haven't had one lick of problems since. Give that a try.
Hi,
Just updated to 3.1 yet the Asus email app still will not show inline or embedded images in emails. It saves them as attachments.
Things i have tried
Sent the email from exchange to my gmail and viewed. Images will show
downloaded 3rd party app "Touchdown" Images will show"
when i click show pictures, images still won't load.
tried deleting my account and reloading it.. Nothing
updated from 3.01 to 3.1 and still nothing
Im running out of things to test as to how to fix this. This has to be a decent issue because it should affect everyone that uses the standard email app on honeycomb for exchange should be having this problem and if not can you think of anything you have done to fix it or that would be different to my setup.
Items to note:
My exchange account is on 2007
using stock ROM not rooted
I got the Honeycomb 3.1 update this morning and my first expectation was the email client got fixed! It was not. I'm kind of sad/dissapointed.
The email client still does not display the embedded pictures correctly.
I have 2 Exchange accounts, and the strange thing (from my own setup here), one of them actually works displaying the embedded pictures after the 3.1 upgrade.
The other one still does not work.
I believe the one that works is an Exchange 2003 account. The one that does not work is either Exchange 2007 or Exchange 2010 account. But I know its newer Exchange for sure.
Previously both did not work. So, they did fix something, but not all.
GMail client works great, no issue with the embedded image.
The other issue the email client still has, and not fixed, is that it still stops working after the tablet loses its connectivity for certain period of time. When the connection is established again, the email client will stop working and simply shows the spinning circle without any ending or fetch any new emails.
After the 3.1 upgrade, the same issue is still there... sad...
Its dissapointing in many ways because i bought this tablet for work purposes and the most essential iteam on the tablet fails to function correctly.
Its obviously able to be fixed because other email clients like touchdown dont have this problem. The reason i dont want to use touchdown is that i should not pay 20 bucks for the priverlage of this issue being fixed. Also thw stock widgets are much betterthan touchdowns.
Yes. Highly disappointing. May return this piece. I know Asus and their updates. Worse than Samsung.
Update? Why?
I really like the idea of the asus transformer, i did not want to get an ipad2 but when the simple things dont work the way they should it gets frustrating. Its not like the emailapp is re inventing the wheel. How can third party apps get it right but not ASUS.
Even my htc desire using htc mail works fine and show inline pictures without fuss.
don't be mad with Asus. The email client is Honeycomb built in native email client.
The one Asus built in only the home screen wigdet (that shows the number of unread emails).
What is the difference between the stock email client and third party email clients that make ebedded images work?
I noticed a issues log on google android website that this issue has been going on since 2008.
If google want to provide a os thats geared to business to steal market share from RIM you would think that something as simple as fixing this would be some kind of a priority.
Spoke with Asus. They were able to replicate the issue with their own exchange accounts. All they said was they don't control how the stock email client works nor can change it and it would be up to Google to fix it.
Android issue since before android was android:
http://code.google.com/p/android/issues/detail?id=1180
All,
I have a new Galaxy S II that is rooted, and has 2.3.5 (XWKI8) installed.
I'm having an odd issue with my work exchange account. So, I set it up using the default email client ... no issue. All works fine, along with contacts and calendar.
Usually by the next day (no specific timeframe has passed, it varies) , my email no longer syncs, and the email client keep popping up a "refreshing" message at the bottom ... constantly. email appears to no longer work.
Next, I delete the account, recreate it , and all works fine again until, the next day when the same symptoms appear.
Next, I deleted the account completely yesterday late day, and went and downloaded a paid version of Enhanced eMail, and set it up. setup perfectly and all worked just fine. Once again, the next day (just before noon today) my email halts updating and enhanced email shows the refreshing icon in the top right ... constantly flashing and trying to update. but no updates.
Any thoughts or suggestions ? Had always worked fine on my previous phone (iPhone 4)
Everything else on the phone works perfectly, but this is beyond frustrating to a guy who get/sends 300+ email a day.
Any help would be appreciated.
I have had a client call our help desk on more than the one occasion with his htc desire. I believe it to be an intermittent android issue that max not necessarily effect all handsets...
sent from t'internet
Hi
I had a similar problem with contact sync. Some contacts just did not sync which resulted in no sync at all.
Exchange ActiveSync is based on https communication. The commands are sent via PUT to the server. If they where above a certain size the server answered with error 413 and sync stopped (no error message on the device, I sniffed the network traffic on the server). Solution was to increase the UploadReadAheadSize in the IIS Metabase on the server running ActiveSync. No problems at all from then on.
For details on doing this on the server see http://technet.microsoft.com/en-us/library/cc737382(WS.10).aspx. (I have set the value to 500000).
br