Well my cold response without having time to really think about it is that your computer must still have some bits of the old program on it.
Try going into control panel> Add/remove software and scroll through the list.
If u see anything to looks like it might have somethign to do with JKA uninstall it. Then try installing it again.
If it is not in the list then your Registry mighy be F-ed up in which u will need some type of registry cleaner program.
I dont know what is the best registry cleaner out on the net but search for one on
www.download.com
Run one of those programs to clean your registry of any mistakes it might have. Then try installing the program again.
Disk 0...wow thats trippy