If your mail app checks for new messages more than once every 10 minutes, the app’s access to your account could be blocked. There are many email clients through which users can easily manage their tasks of emails, but sometimes for advanced features users want to change their email client. Make sure your mail app isn't set to check for new email too frequently.Try signing in directly on the Gmail app. Latest Messaging and Chat category with a new technology in (57.1 MB) Safe & Secure to download for you by Mozilla Organization. The email client's sign-in method might be insecure. Install Thunderbird for Mac full setup on your Mac OS X 10.9 or later PC.If the tips above didn't help, visit and follow the steps on the page.If you recently changed your Gmail password, you might need to re-enter your Gmail account information or completely repeat your Gmail account setup on your other email client.Allow less secure apps: If you don't use 2-Step Verification, you might need to allow less secure apps to access your account.Important: If you sign in with OAuth, use your regular Google password. Recently in my Postbox app (which is based on the OpenSource Thunderbird project), I started getting repeated login errors coming from my Apple Me.com account.Use an App Password: If you use 2-Step Verification, try signing in with an App Password.
If you have these problems or can’t sign in, first check to make sure you’re using the right password.
