Well, that sux
I've looked up similar issues and nothing seem to come up. Perhaps it was a perfect storm that created the problem. I'm still of the mind that something was overwritten and Windows is not deleting the offending file because both pieces of software (and maybe something else) use the same file. I have two more idea's.
The first one is to remove both programs using this (link
). Delete absolutely everything it identifies. Uninstall the printer software, the driver and CS3. Go to C:\Program Files and delete Adobe folder after uninstalling. Do the same with the Canon software. Next, reboot and run CCleaner again (Registry and Cleanup). Reboot again. Install just Adobe CS3. Do not open programs yet. Go here (link
) and install all updates. Every one for CS3. Reboot again (even if it doesn't ask you to). After reboot, does CS3 start? If no, then the problem may not actually be the Printer software but some other misconfiguration. If yes, you're going to have to install 'just' the Scanning software and the print drivers themselves. DO NOT use the setup installer to install the print drivers. You'll want to install the Printer manually and point it to the CD for the drivers. Windows may actually have drivers for that printer.
If the above doesn't work you may have corrupted permissions, ownership, registry or even more serious problems like an undetected rootkit (virus or trojan). In which case, I would backup everything and start from scratch. The printer software and drivers should be the very first thing you install after doing so. Then updates, then CS3.