i can't boot if i do not put the dvd. help!

Boot into the install/repair disc and wait for it to load
Choose “Repair my computer”
Select “Command Prompt”

Type “diskpart” and press enter. Do not type the quotes.
Enter “list disk” and note the number of the disk you want to install on.
Enter “select disk n” n is the number of the disk.
Enter “list partition” and note the number of the partition you want to install on.
Enter “select partition n” n is the number of the partition.
Enter “active”
You can now close the command prompt and re-attempt Startup Repair.

lovelycabelinga said:

i did the start-up repair already, two times. still i can't get to boot without the dvd.
the message still appears "operationg system not found.
regarding the boot loader, how do i check if that's installed? so that i know if that's the root of this problem.

Try running startup repair three times.
It can only do one BCDEdit command at a time, and usually takes three times to work.

As mentioned before, make sure the partition is marked 'Active'.

Give us a snip of your Disk Management.
How to Post a Screenshot in Seven Forums

If all else fails do an Upgrade install, this should fix the boot manager.
Repair Install - to Fix Windows 7

You're welcome. Glad we could help.