outlook error after migrating mailbox

[TKE402]

hi,
i am testing migrating users and mailboxes from another forest/organization
and when I try opening a mailbox of one of the test users, I receive an
error. The error is "unable to open the default folders". There's an option
for more information but this more information references trying to open
outlook in cached mode from within terminal serverices which is not the case.
If I open the mailbox without cached mode than it works fine. Any ideas why
cachec mode doesn't work after a migration?

Thanks,

TKE402