Last year around (Oct 2010) we upgraded from Exchange 2003 to Exchange 2010. Clients that archive locally using auto archive settings are set from 30 to 90 days. Few to none messages are getting archived by clients. This started happening since the migration. This appears to be happening enterprise wide within the organization. What processes on the Exchange 2010 server would scan all the messages and change the modified date? When i list the messages within Outlook the modified date are in batches. Also to note that Anything from last year Sept to end of December 2010 have batches of modified dates for Jan 2011 or Feb 2011. Now sure some messages would get modified by forwarding, copying, moving the messages. But not all of them apply to these circumstances. This happens on all flavors of Outlook and it happens on clients that don't have any third party snap-ins.

Basically, anything that changes the messages will cause the property to change, as the actions that listed in the “More information” section of the KB 295657, including mailbox moving James Luo TechNet Subscriber Support in forum If you have any feedback on our support, please contact tngfb@microsoft.com Please remember to click Mark as Answer on the post that helps you, and to click Unmark as Answer if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.