I believe you'll have to remove it manually. Go to program files/steam/steamapps/common And delete the ENTIRE GTA IV folder. Don't forget to close steam whilst doing so. I don't think that there is another solution to this, so unfortunately you'll most likely have to redownload and reinstall the game again.
Greetings everyone on this forum, I've installed the ICEnhancer for the 184.108.40.206 version of the game recently, but since the 220.127.116.11 version offers better graphical effects I want to try it out as well. However, difficulties have crossed my path.
When playing on the 18.104.22.168 version of the game, I encountered the graphics card recognition problem. This was simply solved by adding "-norestrictions -nomemrestrict" to the steam startup line. The game ran perfectly fine, even with the ICEnhancer installed. However, patching to 22.214.171.124 changed this; Even though the "-nortestrictions -nomemrestrict" was still there, I had the same problem as before. I googled a bit on the intwerwebs, and found out two different strategies: Making a commandline.cfg/commandline.txt with the same parameters in it, or making a shortcut to the 'LaunchGTAIV' program, again with the same paramameters. But none of them worked. Has anybody encountered this problem aswell?