USB flash-pen drive doesn't work after write protection removal

Hello,

I followed the instructions on how to remove write protection to my usb flash drive but after I set the value of the "Writeprotect" key to 0, my usb icon stopped showing in the "My Computer" folder, and now it doesn't work in my or any other PC. I tried to uninstall the drives from Device manager but no result.

Other usb devices work on the same port, so something happened with that particular device.

Please help me.