What to do? I have uninstalled, reinstalled and rebooted...my computer doesn't see my external harddrive. Everything else seems to be working fine. The external harddrive is working fine. What can I do?
You probably do not have enough resources available for the device to work properly. Were there any drivers associated with the install?
If it is seen at all, go into the device manager and try to alter the resources allocated to it.
Alternatively, unplug the device and restrat your computer and go into the BIOS setup. Disable any devices you don't need, like serial ports, parallel ports, etc. Most people do not use serial ports any more and many don't use parallel ports either, but if they are still enabled and still take up resources.
Restart and computer and reattach device as you normally would.
Error code 10 means Window thinks the device is either not present, not working properly, does not have all the drivers installed or they are not installed correctly or got corrupted or the hardware card itself is damaged.
External firewire cards are finiky to say the least. To rule out the drive's interface card, swap with another if you have it or try in another computer. The good news its unlikely the drive and its data are damaged, just the interface card.