Question : Old address/mapping cached in Outlook clients

We just built a new Exchange 2010 server and are have migrated all of our clients mailboxes (via .pst from our former server).  We also replaced the previous AD/domain controller.

Many of our clients are experiencing the same problem.  When  typing a name which auto completes in the to field.... it is surrounded by 'username'; and proceeded by a semi-colon.  When attempting to send a message to that client (which does resolve) it comes back  undeliverable and says the email address could not be found.  However, if you click the "To:" button and pull the same name from the address book and send it that way it is delivered properly.  Once this is done the same problem does not occur again for that user.  I believe the names/addresses from the former server are somehow being cached in out local Outlook clients.  

Has anyone else experienced this and is there a way to purge this data?

Answer : Old address/mapping cached in Outlook clients

Hi,

Refer this:
http://support.microsoft.com/kb/287623

Hope this helps,
Shree