crash while installing parallels tools

Parallels ver3 build 4560 crashed twice while installing parallels tools.

In the first installation I tried to use parallels to control my bootcamp partition. I got the message that parallels tools were being installed and suddenly the program unexpectedly quit.

I then used parallels to install a fresh copy of windows on a virtual hard drive. The installation finished with no problems, but when I tried to install parallels tools the program quit again.

Any ideas?

Thanks