After a cross-forest migration of Users from an Exchange2003/Server2003-Do
main into an existing Exchange 2010 Environment, we have problems with some Outlook Clients.
Computers and Users were migrated to the new domain, together with the corresponding Mailboxes.
Nearly everything runs fine, but on some Outlook Clients there seems to be an old cache entry for mail contacts: if we try to send mail from one (migrated) user to other (migrated) users, the "To:"-address is correcly recognized as "user name <email@example.com>", but mail bounces with the following error:
#550 5.1.1 RESOLVER.ADR.ExRecipNotFound; not found ##
the recipient does not have an X400 address but only normal SMTP addresses
on the client side (sender) we have taken the following steps without success:
- deleted NK2 cache file
- disabled Exchange Cache mode
With OutlookWebAccess everything is fine.
also if we completely remove the User-Profile in Outlook (on the client PC) and add a new Exchange Server connection, the problem is solved.
What else can we try? Is there another cache somewhere in the outlook profile?
I do not want to remove/add every Mailbox in every single Outlook on every single PC by hand...