Issue: The error message Username or Password Incorrect is displayed when trying to sign in to Gmail.
Reason: This is typically caused by Google blocking some less secure third-party applications.
Solution: Change your settings to allow less secure applications:
- Log on to your https://myaccount.google.com/.
- On the left pane, click Security.
- On the bottom of the page, in the Less Secure App Access pane, click Turn on Access. If you don't see this setting, your administrator might have turned this setting off.
- If you still can't sign in to your account, see https://support.google.com/accounts/answer/6009563.