This may not be a solution for you but I had the same problem and solved it like this. First go to Canons Rebel XT download site (do a google search on canon rebel downloads and it's the first hit) Then choose your OS (Operating system) in the pull down menu. If it's XP then the first download you'll see on the list is for WIA560EN.exe
which is the drivers you need. (if it's Vista it's VU600EN.exe
) Install whichever drivers you need and make a note of where your computer has stored it. In my case (XP) it was a file called EOS 3KRN in the Canon folder.
Now connect the camera to your computer and go to Control Panel and select 'Add Hardware'. The camera should show up with a yellow question mark on it. Go through the 'install new hardware' process and choose (I can't remember the exact words) 'I know where the files are located' or words to that effect. and 'browse' when it wants to know where the drivers or disk are located. When it asks where the drivers are located choose browse and go to My Computer, then C drive, then Program Files, then Canon, then EOS 3KRN (or whatever your downloaded drivers were called depending if its XP Vista or Mac etc) Choose this as the file Windows needs to look at to find the drivers. After a few seconds it finds the drivers and installs the camera drivers correctly and your camera is now ready to work with the computer. That's it.
It looks quite complicated written down but it's not that difficult really. Hope that helps :) If you're confused by the directions I'll try to make it clearer