hi there jimmyc_1
sounds like you still have SH3 Files from a previous install ensure theres no SH3 files on your computer also any SH3 Mods you have unpacked including the Commander Mod even the SH3 folder in your documents folder if that has your campaign career Campaign save copy it to a usb stick then delete it now reinstall SH3 all should be fine run SH3 then it will make a new SH3 folder in your documents for your Campaign
reinstall the Commander Mod
then just delete the new one and replace with SH3 folder on usb stick with your career save on and your good to go
please let me how you get on
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