Check in the device manager to see if the Midiman Midi driver is located in Universal Serial Bus Controllers. Then check to see if it is also in the Sound, Video, and Game Controllers. If not, you'll need to manually install the rest of the driver.

Go to Add new hardware - select from list - Sound, Video, and Game Controllers - Have Disk. Find the location of the drivers (either on your CDrom or a directory on your hard drive where you unzipped a downloaded driver. The install will ask the computer to be restarted, and you should be able to use it at this time. You may want to confirm that its working in the Windows control panel under Sounds & Multimedia - Audio - Midi Music Playback. This will show if the driver is installed properly if it is displayed in the list.