I get error 11 on my xbox

This seems like a bad drive, which has happened to 2/3 of my OG Xboxes. If the console is modded, try going to their troubleshooting page to see what might be wrong. If not, try replacing the IDE cable. If the drive is not getting power, try replacing the drive power cable. From what I have experienced, you might be screwed. There could be a problem with the DVD drive motherboard or console motherboard as well, maybe from a un-removed clock capacitor.