After the large WIN10 August upgrade my hotmail account has stopped syncronizing in WIN Live Mail. The problem is 'only' for my Hotmail account. I have another (not Hotmail) mail account. The sync for this works fine also after the WIN upgrade. I have tried to restore to a point before the WIN upgrade. That did not solve the problem. The Hotmail account works ok when I access it via Hotmail.com. This is the error message I get when I try to sync in Live Mail:

Der kan ikke sendes eller modtages meddelelser for kontoen Hotmail (barbro_01).
(in English: no messages can be sent or receceived for account Hotmail (barbro_01))
Servererror: 3219
Server: 'https://mail.services.live.com/DeltaSync_v2.0.0/Sync.aspx'
Windows Live Mail Fejl-id: 0x8DE00005