I have an odd issue where Outlook 2007 stops updating subfolders from Exchange 2010 after migrating from Exchange 2003.
Here's the issue:
1 - I migrated from Exchange 2003 on an SBS 2003 server to Exchange 2010 on a seperate 2008 R2 server. All exchange roles should be moved (OAB, OWA, etc) unless I've missed something along the way.
2 - While both servers were still up and running, I opened outlook and let it reconfigure itself and point to the new server. I tested sending and receiving, no issues internal or external.
3 - I then disabled the Exchange services on the SBS server, and retested, again, no issues.
4 - Now I'm having random issues with subfolders not updating properly. If I close and reopen outlook, the folders update. But, if I stay in outlook, after awhile, it stops updating. As a test, with one user, I recreated her Outlook profile. It then worked, updating those folders for about 9 hours, before it stopped again. If I do a manual Send/Receive, it is slow, but it completes without any error messages. However, if you look in the lower corner where it says "This folder was last updated", that time doesn't change, until I close and reopen outlook (at which point, all the missing mail also appears).
This user is running in Cached exchange mode, with a very large inbox. OWA and her iPhone update correctly at all times.
I have verified that the mailbox size limits are disabled on the Exchange 2010 server.
I have seen this issue with at least 2 people, and I'm guessing others just haven't noticed. One of the mailboxes is less than 2GB, so I don't think it's size related.
As a side note, I do have a user with Outlook 2003 that is having another issue, that may or may not be related...I'll post it here just in case, but I'm not certain it is really pertinent:
She has issues accessing shared calendars that she has permissions to. If I remove the shared calendar, and re-add it, it works fine, for awhile. At some seemingly random point, she loses the ability to open SOME of the shared calendars (and it's different ones every time). The error is: "The connection to the microsoft exchange server is unavailable. Outlook must be online and connected to complete this action." Outlook shows as online, and mail will come in while this error is occurring.