One gmail account stays in red

I have 2 Gmail accounts and 1 Yahoo mail account being checked by X-notifier. For a long time now (months), one of my Gmail accounts has been in red. The other 2 email accounts are good.

A long time ago I'd seen this problem but it self-corrected when X-notifier updated. But then it re-appeared (and affected a different Gmail account iirc).

I have uninstalled the app, restarted Chrome, downloaded a fresh copy of X-notifier and imported my files, but the same Gmail account stays in red. The other Gmail account and the Yahoo email account still work fine.

I have confirmed my UID and password for this Gmail account but it still stays in red on X-notifier.

Windows 10 x64 Pro.

Google Chrome Version 50.0.2661.102 m (64-bit) is up to date.

 

And now, it has somehow fixed itself!

So disregard the above comment.