We recently (4 months ago) migrated users from Exchange 5.5 to 2003. We have
been trying to turn off the old Exch 5.5 server now that no one is on it and
everyone is migrated.

Each time we turn it off, we have a several users having issues with
calendaring and setting up meetings. Turning the old 5.5 server up fixes the
issue. It appears that Outlook, in addition to using free/busy data from the
2003 server, is trying to also contact the old Exch 5.5 server's free/busy PF
area. In a few cases, we found that having them browse the new public folder
structure on 2003 with the 5.5 server still up on the network seemed to up
their profile and they were good after that.

We have try several of the profile cleanup tools and have completed created
new Outlook profiles with no improvement.

Where would this information to the old Exch server free/busy data be
stored? Would it be in the User's profile or in the Registry? Since
creating a new Outlook profile does not fix the issue, it can't be there.

Any help is appreciated.