Hi,
I managed to play ANNO 1800, the day of purchase (through Steam). But the next day I try to start it and I get an error message that says the is a problem authenticating the ownership of the product.
The steam account is the same one I used at purchase and the ubisoft account is the same on initial play.
Please advise.
Hey @MrGreendew1
For queries on Steam game issues which you mentioned, we generally advise you raise this via the Steam forums.
As this seems like an account issue, however, I can inform you that authentication errors typically pop up when you're trying to start the game with the wrong Ubisoft account.
Game activations, once you launch them for the first time, are bound both to the Steam and Ubisoft account. Once you relaunch this in future, you would need to log in with the same Steam and Ubisoft account in order to play.
If you have any issues remembering which Ubisoft account you logged in with the first time, you would need to create an email support case for the team to look into this further for you.
I hope that helps! 
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