Enabling Email Verification
TeamCity administrators can enable / disable email verification (off by default).
If email verification is enabled on the TeamCity server, the Email address field in the user account registration form becomes mandatory. When an address is added/modified, the users will be asked to verify their address. If the email address is not verified, TeamCity will display a notification on the General tab of the user account settings.
Verified email addresses will be marked with a green checkmark on the Administration | Users page.
To enable email verification in TeamCity:
Navigate to the Administration | Authentication page.
Select the Enable email verification option (off by default).
Save your changes.