Folders redownload when connecting to Exchange
Abuse history
Answer
Since you are using an Exchange Server account, and since you do not use one of the systems for a period of time, every time you try to synchronize the changes, it would take time to make the necessary changes to the Exchange Server.
When the progress bar shows that some of my folders are re-downloading or uploading the full contents of the folders, do you see duplicate folders or emails in Outlook 2011?
If not then there are should not be any corruptions.
In case if you want, you can create a new Identity in Outlook 2011 and check if it helps:
Step 5 in the following article is for creating a New Identity:
http://support.microsoft.com/kb/2360509
You may also reduce the amount of data on the Exchange Server by moving older emails from the server locally to the system.
