In my 30+ years of installing and upgrading software on personal computers, the Parallels upgrade from 3.x to 4.x has got to be the worst upgrade I have ever experienced. Orders of magnitude worse than anything else I have ever experienced. Three hours to migrate my old VM to version 4.0. Three hours! Multiple "an error occurred" messages, each with a transfer to a generic "installing/upgrading 4.0" webpage that has nothing relevant to the problem I am experiencing. I finally complete the upgrade. Then guess what, I get into a "new hardware found, install drivers, you need to reboot for new driver to take effect, new hardware found, etc, etc, etc, etc..." loop that I cannot break out of. Three hours to migrate a vanilla Windows 2000 VM, and it doesn't even work when it is done. Awful quality software. Absolutely awful.
I abandoned my hope of upgrading my existing VM, and instead tried to create a new VM. It didn't work either. After the first reboot during the install, I got a fatal Parallels error. I duly described what i was doing at the time, and even entered my email address, hoping that I would get an email copy of the trouble report along with the trouble ID. I was wrong. Now I have no idea of the trouble ID for my problem report. It is a shame that Parallels has no concept of basic customer service techniques. I am now in the process of loading up Sun's Open Virtualbox to see how that works. So far, no problems whatsoever.
Well, at this point I think I'm moving on. I cannot get the Parallels 4.0 VM to work reliably. I tried Sun's Open Virtualbox and VMWare's Fusion. Both work fine -- much, much more reliably than Parallels solution. In some respects, I have sympathy for the Engineering and QA people at Parallels, as they may be getting the brunt of the criticisms for the 4.0 disaster, when it was more than likely a Business Manager who pushed to release the product before it was ready. I'm not going to ask for a refund of my upgrade money. I'll donate that to Parallels in the hope they can get their act together soon.