I did the following: 1 - downloaded new version 2 - started old version, uninstalled old parallels tools 3 - shut down (start menu, "turn off") windows 3a- quit parallels 4 - installed new parallels 4a- replaced dock icon 4b- started parallels, it found my 3 virtual machines (xp, linux, 98) 5 - booted xp (went fine) 6 - let it find "hardware" 7 - installed new parallels tools 8 - rebooted - black screen hang... 9 - started in safe mode, went to uninstall parallels tools as per FAQ - NOT THERE! 10- still would not boot - I tried quitting parallels, rebooting, nothing worked 11 - started in safe mode, installed parallels tools IN safe mode 12 - XP booted normally, seems to work fine. ...for anyone who is having a similar problem.