I have 3 hotmail accounts on windows live mail. One works, two do not. I checked spelling, etc. This is the message I get for each of the two :

Unable to send or receive messages for the Hotmail (clean-it) account.

Server Error: 3204
Server: 'https://mail.services.live.com/DeltaSync_v2.0.0/Sync.aspx'
Windows Live Mail Error ID: 0x8DE20003

I have windows 10.