Gmail unusual activity, does it mean a successful connection has been made?

Question

I've noticed an unusual activity on my Gmail account:

 Inconnu     Viêt Nam (fpt.vn:118.71.51.26)  14 nov. (il y a 1 jour)

What does it mean exactly?

1. that a successful login has been made with full access to my account;
2. a successful login has been made to the account, but Google has blocked the access before any access were possible;
3. only an attempt, but the credentials have not been validated.

... or something else?

Answer 1

From Gmail Help:

Last account activity shows you information about recent activity in your mail. Recent activity includes any time that your mail was accessed using a regular web browser, a POP1 client, a mobile device, etc. We'll list the IP address that accessed your mail, the associated location, as well as the time and date.

That means your mail was definitely accessed. Gmail will not list any unsuccessful attempts, therefore you should immediately change your password and follow the security checklist!

Answer 2

I would like to add that enabling 2 factor authentication on your Gmail account is a great way to prevent unauthorized access to your account. You can see more information here.

It's an extra step, but it's one that significantly improves the security of your Google Account because it requires the powerful combination of both something you know—your username and password—and something that only you should have—your phone. A hacker would need access to both of these factors to gain access to your account.