W7 won't start-up without install-dvd


New Member

I have a problem starting up W7 in dual boot.
I did a clean install of the W7 RTM on the second partition of my (sata) HDD.
After installation I didn't get a dual boot menu to choose my OS (Vista or W7)
I forced a dualboot menu with Vistabootpro, but when I choose the W7 option, I get an error telling me that "the digital signature of winload.exe can not be verified"

After that I accidentally discovered that W7 can start-up when I have the install DVD in my dvd-drive.
It prompts first with the massage "To start from DVD press any key"
Then when I don't press a key it starts booting W7.

How can I get rid of this procedure and ad W7 working in a dual boot menu?