Won't install

Trying to install Vista Ultimate on my Mac Pro using Parallels 4.0. It works to a point...The process always stops at a black DOS screen with the text,

"No Systemdisk. Booting from harddisk
Cannot load from harddisk.
Insert Systemdisk and press any key."

The Vista Ultimate disk is in the tray, but for some reason it isn't acknowledging the disk.

I have...
MacPro
Quad-Core Intel Xeon
2.66 GHz
1 Processor
4
Cores
3 GB Memory
200 GB available on drive
Snow Leopard, 10.6.1

I did the search, and while a couple Users had this problem-- there was no response from the community. Also, the 'Watch A Demo' is only a commercial for the product, so it was no help...So, I'll try my luck here...

 

Hello,

Check if the disk that you are using is a bootable disk or not. If it is a bootable disk then click on the link below to follow the instructions given in the article.
http://kb.parallels.com/en/4917