You can give this a try. Copied it from another post and it worked for me.
If you've backed up the Pro 668 Folder from your scanner, locate it and find the "inf" folder. It will only work if you have it on the PC. Open it and copy the "RadioShack_PRO-668.inf" file somewhere easily accessible like the desktop or just keep it there and remember how to get to it.
1. Click on the Start Menu, Click on power, then hold the Shift key and click Restart at the same time.
2. After the PC restarts click on Troubleshoot, click on Advanced options, click Start Up Settings then click Restart.
3. After the PC restarts Press the number 7 to Disable driver signature enforcement. Windows will now load.
4. Locate the "RadioShack_PRO-668.inf" Right click on it and choose Install. You'll get a warning but go ahead and install it.
5. Plug in your scanner, right click on Start Menu, choose Device Manager.
6. Expand "Ports (COM & LPT)" If you have more than one device here you'll have to figure out which is the scanner and then right click on it. choose Update Driver Software
7. Choose "Browse My Computer for Driver Software" then "Let me pick from a list of devices.."
8. Check the box "Show compatible hardware" Click on "RadioShack_PRO-668 Serial Device" Then click next. You should get a screen that says "Windows has successfully updated your driver software"
I hope this works for you.
