Well well well...
once again.
After the message box popped up, hit ok. A folderbrowserdialog will pop up. Now you will have to select your COD 6 GAME FOLDER. By default:
Original: Device:\Program Files\Steam\SteamApps\common\call of duty modern warfare 2
C:\Programs(or program files)\Steam\Steamapps\common\ call of duty modern warfare 2
So basically, you have to find your steamfolder in the folderbrowserdialog and expand it.
Expand SteamApps folder.
Expand common folder.
SELECT call of duty modern warfare 2 folder.
Hit ok.
Now you will have to restart the program, it will automaticlly close telling you to restart the program.
-> Fixxed.
Reason why this error appears:
To make the singleplayer hacks work, a streamwriter is used to edit your config.cfg.
It is trying to edit -> THE PATH YOU'VE SET\players\config.cfg.
If it cannot find the config.cfg, or an error appears, it'll say "You did not set your cod6 folder path correctly.".
So make sure you actually selected the correct folder.
AlterIW: Whereever you installed CoD :P
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I do hope you all get it now. It is NOT a difficult problem and an obvious error.
Leave this topic so I can link further questions to this topic.