Gmail - Detecting Suspicious Account Activity

Google introduces a new feature in Gmail to notice Gmail user when Google detect suspicious login activity in the user Gmail account. If Google detect unusual activities going on in the account, Google will post a warning message, "Warning: We believe your account was last accessed from…" along with the geographic region that Google can best associate with the access. This is done by detecting the IP address relate to geographical location.

Also, Google has previously rolled out feature for user to detect their previous login IP address and location. It is located at the bottom of your Gmail account, where it says Last account activity: 49 minutes ago on this computer.  Details. 

Click on details to see the historical activities details

Google suggest that if you think your account has been compromised, change the password immediately from the same window. Or you could click 'Dismiss' to remove the message if it is legitimate access by yourself or someone authorized.

My thought is, if the scammer or intruder use your account, I am not sure if they are also seeing this warning messages. And if they do, they might change the account password. However, you could use this 'I cannot access my account ' to retrieve your password or regain your account back through this link.

As for now, Google has 6 troubleshooting options for your problems.

1) I forgot my password
2) I forgot my username
3) My account has been compromised
4) My password doesn't seem to be working
5) Loading issues
6) Another error or problem

Notice above that 'My account has been compromised' is one of the option. That may means that Google has procedure to help you regain back your account.

Also note that as for today, Google has not implemented this security measure in Google Apps email.