Apple Mail App not working with iCloud
This is a recent problem that the apple @mac account has gone off-line and is no longer downloading new messages, or sending new mail.
Message says: This Mac can't connect to iCloud because of a problem with (my e-mail address @mac.com).
Open iCloud preferences to fix this problem.
When opening iCloud preferences it requires my Apple ID but answers back "An unknown error occurred'.
The Apple ID is correct. I can sign it via the Apple webpage and check my mail.
I can also still receive and send mail from the @mac account on the iPhone
Anybody has or had similar problems? My iMac is 2011 27" with OS High Sierra.
Thanks.
iMac 27″, macOS 10.13