Factorio shows different person's username

[insofacto001]

My factorio game (and DLC) are bound to my steam account and I've been playing for a while now.

However ever since playing on a friend's server my username seems to have changed to HIS username. It makes no sense at all. My steam name and my factorio name are not reflected in the games UI elements. It just shows my friend's name (or perhaps his server name when we played on it).

Its superficial but very annoying. Every achivement shows my steam name on steam, but my friend's server name in game. It can be seen while hovering over any game item under the label "Last User".

What on earth is going on? Any help is greatly appreciated!

[eugenekay]

From the Main Menu, navigate to Settings --> Other:

09-24-2025, 21-57-50.png (59.67 KiB) Viewed 181 times

Then "Log Out" and "Log In" again:

09-24-2025, 21-58-43.png (8.64 KiB) Viewed 181 times

It sounds like you may have inadvertently downloaded your friend's player-data.json file from the Server. This file contains a private Token which identifies the User. For safety sake, your friend may want to visit Factorio Profile and use the "Invalidate" button.

Good Luck!

[insofacto001]

Thanks for your reply.

I've clicked Log Out, and then Log In and it says that I'm authenticated as my username.

However mousing over any item in the game still shows "Last User: " with another user's name.

At this point should I uninstall Factorio from steam entirely?

Thanks for any help.

[eugenekay]

However mousing over any item in the game still shows "Last User: " with another user's name.

At this point should I uninstall Factorio from steam entirely?

Thanks for any help.

The “Last User” data is stored within the save file, and it reflects the Username that last changed that Entity. This is meant for Multiplayer, where it is helpful to know Who built/changed/griefed/fixed a section of the Factory. There is no easy way to change it across the entire map without touching or rebuilding every entity, which may have unintended side effects (such as destroying the whole factory). It does not have any tangible effect on Singleplayer gameplay and can be ignored. In technical terms EVERYTHING is Multiplayer for consistency sake; it just happens that the “server” and “client” are the same Factorio instance.

Or start a New Game. No need to un/install.