If you receive the following error like above upon launching the game then please download the fix below and extract it in your InfinityMU folder where main.exe location is and replace the old files with the new files from the archive.
Download Fix: [Click Here]
Instructions: paste and replace with old InfinityMU files.
Problem was found to be caused by registry alteration by Webzen (official Mu client) and here we provide custom fix for those who experience such problem. It mostly happens if you have installed official mu webzen client on your computer and you are trying to play InfinityMU.
ye: Enjoy