If your mail app checks for new messages more than once every 10 minutes, the app’s access to your account could be blocked. Make sure your mail app isn't set to check for new email too frequently.

Try signing in directly on the Gmail app.

The email client's sign-in method might be insecure.

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.Use an App Password: If you use 2-Step Verification, try signing in with an App Password.Update your email client to the latest version.If you want to create another email address that uses the same inbox, sent, items, and contact list as your existing. To see all your email accounts, calendars, and contacts in a combined inbox, download Outlook for iOS or Outlook for Android. If you have these problems or can’t sign in, first check to make sure you’re using the right password. Tips: Premium customers can add their Google Mail and Calendar accounts as an additional mailbox.

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