Looking on all posts regarding USB printing, it seams to be a general point that isn't solved for all of you. I will not invest more time on this (1 day to try a lot of hints from the forum is enough), I think that has to be solved from parallels people. By the way: I like the software, all the rest works great (I was using Virtual PC for many years, Parallels is better!). Some informations about the problem: OSX printing is ok with my Canon Pixma MP810. I was not able to get it working with Bonjour in Windows XP. The printer is visible in the connected USB devices, but now way to print. I connected a GPS watch (Suunto X9i) and everything just worked perfectly (data transfer to the tool, even data transfer to Google earth), so it seams not to be the USB integration that isn't working, it's only the printer not working.
The printer is not supposed to be seen by the VM as a USB device. It is a NETWORK printer. You get it working in OSX, then share it (in OSX) over the network, and use Bonjour to find it on the network, and connect to it as a NETWORK device, not a USB device.
Thanks for your advice, but this I've allready tried to do (network printer, bonjour, etc.). The printer is visible in the VW as USB device. Driver installed on XP. Printer not found to install, manual install possible, but printing not working.
Problem solved! After a new installation of XP, I clicked into the USB connected devices and activated the printer, the system "found" new hardware, started to install drivers (I allready installed the drivers before) and now: everything (printer and scanner just works perfectly! Now I really like this software and will buy it, because I can now connect my not Mac compatible devices like Suunto Watches, SonyEricsson Phones, and some more. Just beautiful!