You will receive the failure message "Username or Password Incorrect" when trying to sign in to Gmail. This is typically caused by Google blocking some less secure third-party apps. This can be fixed in the settings.
Change your settings to allow less secure apps into your account:
- Go to your Google Account.
- On the left navigation panel, click Security.
- On the bottom of the page in the Less Secure App Access Panel, 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, learn more about the "password incorrect" error.