When you try to add a new Gmail account in Microsoft Outlook, you encounter the following symptoms:
You are prompted for authentication, and your credentials are not accepted.
You receive the following error message in Outlook:
Your IMAP server wants to alert you to the following: Please log in via your web browser: http://support.google.com/mail/accounts/bing/answer.py?answer=78754 (Failure)
Note If you are using Outlook 2016 for Mac or Outlook for Mac 2011, the prompt and error message may look different, but the method for resolving the issue is the same.
This issue occurs when you try to sync to a Gmail account after July 15, 2014 and Basic Authentication has not been enabled for your Gmail account.
Google has increased its security measures to block access to Google accounts after July 15, 2014 if those accounts are being set up or synced in apps and on devices that use Basic Authentication.
To resolve this problem, enable Basic Authentication for your Gmail account. To do this, go to the following Google website, and then select Enable when you are prompted about whether to let less secure apps access your Gmail account:
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