If you still have a problem with installation Parallels Tool into Bootcamp VM, please: 1. Check if exists file c:\windows\system32\drivers\prl_boot.sys check if exists folder c:\windows\system32\drivers\prl_boot.sys If you find the folder instead of the file with such name you need remove it manually. NOTE, that incorrect manual changing of system folders is very dangerous. Note, that you need change premissions for folder drivers\prl_boot.sys to it. 2. Try to install Parallels Tools again.