Hi Diane, The problem does not lie with the 250th message specifically. If you kill Outlook and open it again it then hangs at "updating cached messages (500/1700)" and so on until you finally manage to update all the headers.
Cached mode creates a local copy (i.e., copy on your computer) of the data stored on the Office 365 cloud.Outlook accesses this cached copy for most operations, and that speeds up response times.Here is the scenario: Executive A is a high-volume, high-density email user in a far city.He easily sends and receives several hundred emails each day, most of them with large attachments of photos or PDFs with embedded photos.Cached Exchange Mode works like this: When the Exchange Server notifies Outlook of a change, the Download timer starts and Outlook delays receiving the change information.
All notifications that occur in the 30 second window of the Download timer are grouped and processed as a batch at the end of the timer, then the timer is reset.The executive in question also uses multiple computers - one in the office and one in the home office, both on the East Coast of the U. Both his computers are configured to get his email from our Exchange Server on the West Coast of the U. The complaint is that it will sometimes take hours for synchronization of the offline folders to take place when first firing up one or the other to check his email.He reports that some emails are delayed by many hours while the cache is playing catch up. All email flows here and then out to the remote office.I have found no logic as to why one folder does and another doesn't!Whilst checking various on options and settings as I have composed this email, I think I may have stumbled across a partial solution.Note that the following blog only works if you are connected to an Exchange server.