It sounds like you have not put the camera in "playback" mode for download.
Make sure the switch on the back is not in video or record mode. It must be in "playback" mode.
If that does not solve the problem, you should consider getting a card reader. Much simpler - you don't need special software and you never have to connect the camera to the computer.
My problem is simply that when connecting the camera to the USB and turning it on, I see "Canon SD450" appear in the "Scanners and Cameras" window. However, a couple of seconds later, the camera powers itself off, and "SD450" disappears out of the "Scanners and Cameras" window. The "Autoplay" window then pops up, but with no programs listed in it.
- Camera battery is fully charged, the camera works perfectly and I can take pictures OK
- All latest Canon software is installed
- USB ports are all fully working (I can connect a mouse to them with no problem)
- I am logged on as administrator
- THe computer has USB 2.0 ports
- No errors recorded in Windows event viewer
I have had zero success looking on Google and Canon's website has a step by step process I would like to follow, if only I could persuade the camera to remain powered up while connected to the computer.
There is a fix floating around to do with modifying a registry setting, but my registry is set correctly. Another fix suggests removing RealPlayer, which I have done.
If anyone has any suggestions I would be grateful to hear them!