Open Chrome, and then go to https://mail.google.com


Click the Service Handler icon


Click Allow, and then Done.


If this icon  does not appear in the URL bar, follow these steps:

  1. Open Chrome Browser and click More Settings.
  2. Go to the Privacy and security section.
  3. Next to Site Settings, click the Right arrow
  4. Scroll down to Additional permissions and click Expand .
  5. Next to Handlers, click the Right arrow .
  6. At the top, make sure Allow sites to ask to become default handlers for protocols (recommended)is turned on.
    Note: Scroll down to the Blocked section and make sure that mail.google.com doesn't appear in this list.
  7. In your Chrome Browser's address bar, enter mail.google.com.
  8. Click Service handler .
  9. Click AllowDone.