I've been getting this error intermittently for years on my iPhone. I've searched the web and found thousands of posts about it. All the suggested remedies fail to work, or only work temporarily. One of the few things that usually works is deleting the gmail account and re-adding it, but this is obviously a PITA and I don't want to do that every week. Does anyone have a fix for this??? Why doesn't Apple or Google do anything about it? Things I've tried: - Deleting and re-adding the account (Sometimes works, but time consuming) - Allowing less secure apps - Going to accounts.google.com/DeviceUnlockCaptcha - Allowing 2-factor authentication (if anything, this just made everything even more annoying) Things I'm not willing to try: - Using the Gmail app (I hate having my mail in more than one place) Anyone else have this problem? Anyone have a solution?