Mac mail (Mail.app) continually asking for Gmail password, then hangs
Greetings everyone.
I've seen this issue reported by several others (recently here), but have yet to see a solution posted.
Issue is this: a few weeks ago, Mail.app started regularly asking for passwords to my Gmail accounts. Then last week it got to the point where Mail could no longer resolve the Gmail account password, and I can no longer receive Gmail via Mail.app.
When I click on the "broken connection" icon next to any of my Gmail account names, Mail opens a dropdown panel with the Gmail password interface. Email address is repopulated, so I click "Next;" then I enter my password, and the dropdown window goes blank, and eventually times out, with the only option is a "Cancel" button, like this:
Per advice posted to others on this forum I tried creating a new user account on my Mac, and when I add my Gmail accounts to Mail.app there, everything seems to work with no issue. I can send and receive Gmail for the first time in over a week. But when I return to my primary account, the issue persists.
I also tried using a beta version of Airmail; it could never connect to my Gmail accounts.
I tried using Spark, and it gave me the error: "Spark cannot access your iCloud Keychain (?!) required to sync your emails. Please restart your Mac and try again."
Any idea how to resolve this situation? It's definitely been disruptive, would love to get this resolved ASAP
Thanks in advance for any help.
—snoqualmie7
MacBook Pro (Retina, 15-inch, Late 2013)
macOS High Sierra v10.13.4