How do I fix Gmail error 400?

The Bad

  1. Get to Chrome Setting.
  2. Click Show advanced settings.
  3. In the Privacy section, click the Content settings button.
  4. In the “Cookies” section, click All cookies and site data to open the Cookies and Other Data dialogs.
  5. In the search box search for mail.google.com.
  6. Click Done.
  7. Refresh the page giving you the error.

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