Privacy Handbuch

GoogleMail (oder GMail) mag eine anonyme Nutzung der kostenfreien Accounts nicht.

Kurz zusammengefasst kann man sagen, dass Google entweder eine IP-Adresse der Nutzer haben möchte oder die Telefonnummer. Stellungnahme des Google account security team zu einer Anfrage der Tor Community:
Hello,

I work for Google as TL of the account security system that is blocking your access.

Access to Google accounts via Tor (or any anonymizing proxy service) is not allowed unless you have established a track record of using those services beforehand. You have several ways to do that:

1) With Tor active, log in via the web and answer a security quiz, if any is presented. You may need to receive a code on your phone. If you don't have a phone number on the account the access may be denied.

2) Log in via the web without Tor, then activate Tor and log in again WITHOUT clearing cookies. The GAPS cookie on your browser is a large random number that acts as a second factor and will whitelist your access.

Once we see that your account has a track record of being successfully accessed via Tor the security checks are relaxed and you should be able to use TorBirdy.

Hope that helps,

Google account security team
Außerdem werden nach einem Bericht von Wired zukünftig alle E-Mails der GMail Accounts in das NSA-Datacenter in Bluffdale kopiert.