Maniaplanet Forum

Then I don't know.

Uninstall the game completely, delete all local data also from your windows user documents Maniaplanet folder, and install the game fresh again.

And: you do not need to indicate your cd key in the game at all anytime.

Now the game crash as soon as I launch it. I try to reconnect with my account. It has crashed since

I tried to reload the game with all the files but nothing to do. The game crash and always tells me the same. "The game key has already been activated"

this is weird.

I would install the regular version of the game that does not need Steam.
If the account is OK on masterserver side, you should be able to play then.

Do you have access to another PC as well? A friend who also has Maniaplanet perhaps?
Then you could try to login with your Maniaplanet account there.

I will try on a different computer and I will contact you