Confusion after dual-boot system has GAG installed


Active Member
Hi all.

I've been looking at various bootloaders, and have been experimenting with GAG but getting some odd results. If you can shed any light on this test case it would be much appreciated!

I have a system with a single disk - XP on partition 1 and Win 7 on partition 2. My plan was to (ultimately) reduce the size of 1 and extend 2 downward, but this of course can cause boot problems without the help of programs like GAG -- at least that's my understanding of the Windows boot procedure.

As an initial test, I left the partition sizes alone and simply installed GAG. Prior to installing GAG, the system used Microsoft's dual booting mechanism, defaulting to the Win 7 system.

After installing GAG, I "added" OSes to GAG's menu (and "saved to Hard Disk" of course) for both of the systems.

However, the result was that when I selected the Win 7 partition (from GAG), I initally got a "Missing ntldr" error. After running the Win 7 "repair" disk a couple of times I now get nothing (just a hang) at that point instead of the Missng ntldr error.

However, if I choose the OTHER OS choice in GAG, I get the old Microsoft dual choice screen that I had originally, and I can then choose either OS from there successfully and both will load OK from there.

Is this one of those EasyBCD to the rescue situations? I'd like to get things straightened out for now as simply as possible, though ultimately I do want to proceed with reducing the XP partition and increasing (downward) the Win7 partition, then ultimately deleting the XP partition entirely and giving all space on that disk to Win7 for now.

As I noted originally, I've already tried to use the rescue disk technique, and only ended up in a more confused position vis-a-vis what I'm seeing via GAG. I don't want to blindly screw around with the bootloaders and possibly get into a place where I can't boot either system at all!
I have no experience with GAG and EasyBCD can only fix problems with W7's bootloader and configure XP's boot files so it'll boot.
From what I've just seen, Binging GAG, it requires each OS to have its own independent install, complete with PBR in each partition.
You previously had a MS dual-boot, which will have put all the boot files in one partition ("system").
You'll need to do independent installs, not allowing W7 to detect XP, not easy to do with a single HDD.