Do you have documents moved to a different drive? This has been a problem since day 1 and they haven't fixed it yet. Extremely odd and infuriating that they didn't but the game does have a metric ton of issues on top of that.
This isn't a problem with the game, it's a problem with the launcher to be fair. Since every other paradox game, and literally every single other game and program I have played/used for... 5+ years? Never had this issue. So It's a mystery how they managed to make such a specific problem.
Reported it ages ago but never fixed. But the game has tons of issues atm so understandable.
https://forum.paradoxplaza.com/foru...d-folder-for-mods-bricks-breaks-mods.1171663/
The Fix
Go into your games folder, for me its: F:\SteamLibrary\steamapps\common\ImperatorRome\game
Open "launcher-settings.json" with a text editor and change
"gameDataPath": "%USERPROFILE%/Documents/Paradox Interactive/Imperator",
to whatever the path of your documents folder actually is. For me its
"gameDataPath": "F:\Documents\Paradox Interactive\Imperator",
Bam it should work perfectly. The fact that it is surprisingly difficult to find this information is... puzzling.
Wish they added an option in the launcher to fix this as a band aid till the real fix or something. At least I'm like 80% sure this is the problem you have.
DO backup the file though. For some reason in the latest versions of the game this... bricks the launcher. No idea why.