I deleted the Exchange Server 5.5 mailbox and have an orphaned offline folder (.ost) file. Unfortunately, I modified the profile and connected to the server with a new mailbox, and now I can't access the .ost file. Can I fix this problem?

Each .ost file contains an encrypted token associated with the profile you used to create the file. If you change the profile to point to a different mailbox, the token in the .ost file no longer matches the profile, and Microsoft Outlook won't be able to open the file. The Microsoft article "XCLN: Restoring from an OST after Deleting the Mailbox" (http://support.microsoft.com/support/kb/articles/q163/5/89.asp) documents this behavior. Unfortunately, no workaround exists.