System Preferences Dock Icon has red circle with 1
macOS Sierra (10.12.4)
It may be related to Two-factor authentication for Apple ID. Tap iCloud to find out.
I'd click the Continue button. It will not begin a process you cannot terminate or undo.
It was pretty opaque, though, wasn't it?
I agree.
Brilliant, thanks its worked for me too
System Preferences Dock Icon has red circle with 1