Windows XP: Problem Downloading Pictures Canon Software

Hello!
I have am having trouble downloading pictures through my Canon camera to my Windows XP computer. I had a Canon SD630 which worked great and downloaded pictures for a while and then one day I plugged in my camera and nothing popped up to download (I'm not sure wha happened). Even though nothing popped up, it still made the sound notifying me I plugged in the camera. I contacted Canon and they gave me instructions for starting different services. When I went into the services and tried to start Canon Camera Access 8, it refused to start and gave me the error saying it cannot be started on the local computer. I scrolled down to WIA and that said Starting, however, it never started. Canon told me to contact Dell and I did. Dell said I needed to call a special number for critical problems, but now I am out of warranty. I found a way to get the camera to download pictures, by Disabling the Canon Camera Access service, that would allow WIA to start. Then, I would sometimes be able to go back to the Canon service, and start it. From there, everything would work fine. However, I want to try and fix this problem so that I don't need to turn services on and off. My Canon SD630died, so I uninstalled all my software and unintalled the camera driver after I bought a SD 1100IS. I installed the software and everything fo the new camera, which is almost identical to the old software; the same problem is still there. How can I fix this?

Thank you for reading this& please try to provide me with a solution.

 

thanks. that is what i will be doing if the problem comes up again. However, I did some more digging online after i posted the question. I saw somethings about the HP Printer software conflicting with the camera software because HP uses twain and and canon uses wia. I decided to uninstall all my HP Printer software and sure enough the canon software started working again and the wia service started on its own. I then went to the HP website and downloaded the driver for the printer. I re setup the printer and both the canon software and hp printer work now.
Shocker right?