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rpanders
User level: Level 1 (6 points)

OS27 Mail with Exchange not-synching

Since upgrading to OS27 my Mac Mail has stopped synching anything I do to an exchange account. For example, it receives messages but then if I read them of flag them this doesn't sync up to the server. I have tried re-building the mailbox, removing and re-adding the account but to no avail. This is extremely disappointing from Apple for what I would think was a major use of the Mail application.

Posted on Sep 21, 2026 4:41 AM

2 replies

razmee209
User level: Level 10 (205,348 points)

Sep 21, 2026 2:23 PM in response to rpanders

rpanders wrote:
Since upgrading to OS27 my Mac Mail has stopped synching anything I do to an exchange account. For example, it receives messages but then if I read them of flag them this doesn't sync up to the server. I have tried re-building the mailbox, removing and re-adding the account but to no avail. This is extremely disappointing from Apple for what I would think was a major use of the Mail application.

It doesn't sync up to Microsoft server not A[[les.

What did Microsoft support say when you reach out to them?

What does their support site say?

djstoopid
User level: Level 1 (9 points)

Sep 22, 2026 8:17 PM in response to rpanders

Exact same issue. It was working fine for a few days, then today I noticed many of my email activities (outgoing mail, archiving, moving to folders, etc…) were not syncing back to the exchange server. Incoming items sync’d immediately, but nothing outgoing.


I tried removing and reinstalled the exchange account, still seemingly not working.

Originally posted at discussions.apple.com/thread/256361832