My friend told me a fix that works. Tested on Vista and Windows 7.
1:Open Task Manager (ctrl+alt+delete)
2:Open Item Manager
3:Open the s4 patcher (dont press start yet)
4:Go back to Task Manager and right click Item Manager.
5:Select "Go to Process"
6:Right click the process (name is random letters and numbers) then select "Properties"
7:Rename the process to whatever you want and press ok
8:Go back to the s4 patcher and press start
After that it should work. I think you have to do this every time you want to play s4 since the Item Manager process in task manager changes names every time you open it.