Here is a small guide (only for Win 10) that helped me. (It may not help everyone).
All changes are at your own risk.
Important !!! – First close all programs –
- Enter „Environment variables“ in the search bar at the bottom left and start
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- Click on environment variables
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- Im unteren Bereich (Systemvariablen) auf “Neu” klicken
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- First assign a name and then click on „Search file“.
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- Navigate to your RoM installation directory and search for the file „Client.exe.ini“ !!! Important. This is not the application file but the configuration file !!!
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- It should then look like this
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- Confirm all windows with „Ok“ and then shut down and restart the computer (please do not perform a quick start)
Now the error should no longer occur. In any case, it has already helped several people.