I know I've helped some people who ran into that by going into device manager when the unit is plugged in and removing it where ever it might appear.
I assume it's a usb device, and I'll assume you have xp because that's all i have to work from hehe.
right click on MyComputer then click Properties, select the Hardware tab and click Device Manager.
Look under Universal Serial Bus controllers and see if you see anything resembling your cameras name in there, it might even have a yellow ? or a red X on it.
If you're sure it's for your camera unistall it there and then unplug your camera and re-install the drivers. Then reconnect your camera and try again.
You might also when you're in Device Manager to look for any other yellow ?'s or red X's because your camera driver itself might show up there, do the same as above for it.
Good luck, and I hope I didn't break your pc in telling you how to do this

DF