I have had two scanners connected to my computer for many years, a Canon FS4000 film scanner and an Epson 2450 flatbed, with no problems with either one. About a month or so ago I wanted to copy a piece of paper and found out that my trusty Epson did not work. I uninstalled the driver and installed it several times with no success. I would go through the install process, the computer would recognize the scanner by its brand and model, then it would present me with a message:
There was a problem installing this hardware.
Windows cannot start this hardware device because its configuration information (in the registry) is incomplete or damaged (Code 19)
My search efforts gave me no help and I disconnected the Epson and connected it to my wife’s computer with no problems.
A few days ago, I needed to scan a slide for a friend and I found out that my Canon FS4000 did not work either. I went through the uninstall-install driver routine with no success. Finally, I connected the scanner to my notebook and did the scanning there. But, I knew there was something strange. Two scanners, connected directly to the computer, on the back panel where there are no possible low power issues stopped working.
After scanning the slide, I disconnected the slide scanner from the notebook and on a whim plugged it to the front USP port on my desktop. To my utter surprise, the scanner driver installed and it started working. Either through a bizarre coincidence, I lost two USB ports on the back, or part of the USB system of Windows XP failed.
More search on Google. Still no help, but some hints. Code 19 means that there is a registry problem and this is due, most likely, the device being defined twice. There were some instructions on how to fix a similar problem for a CD or DVD-ROM drive, but they did not correspond to imaging devices in the registry. If only I could find a way of deleting these devices which, for some reason refused to uninstall. I wrote to support forums, friends, … no help.
Then, I remembered reading about a program called USBDeview from http://www.nirsoft.net and I downloaded and installed it. Sure enough, it displayed all the devices that my computer ever knew, USB flash drives, USB hard drives, cameras, etc. were all listed. After one mishap due to my carelessness (see below) I was able to delete all instances of the Canon and the Epson devices with a few keystrokes. After that, I plugged the Canon, lo and behold, the driver installed and it started humming.
A word of CAUTION here. Be very careful what you delete from the list you see when the program starts. I accidentally deleted my Bluetooth mouse and keyboard and was up the creek. Too swift and not too smart! Go slowly, think twice, then think again before deleting. Nothing you delete is totally lost, but you could find yourself without a keyboard and a mouse, not a comfortable feeling. I started the computer from a power down and the mouse and the keyboard started working again.