My Outlook K3 user had approached our mailbox limit on her laptop. Cached mode and her ost file were working fine. Because she was in the office and on a deadline I disabled cached mode so she could work and complete her project. Afterwards she reduced her mailbox to one-third its original size. I then turned cached mode back on and the rebuild process halts with the 'Mailbox Cleanup' window saying she is over the limit. It cannot finish creating the ost file and I am forced to disable cached mode.
Additional Info: Of my 30 or so laptop users she is the only one with this problem. Her ost file ends at the middle of last week. Her mailbox is well below 50% of our limit. Her pst files are no more than 2 GB. All other systems are running fine.