That's probably because the XP Repair function overrid the Vista MBR. In the attached document, go to the part called "Restoring Vista and dual booting". With EasyBCD (freeware), you can reinstate the dual boot function on your pc. Note that Net Framework version 2.0 at least is required to run EasyBCD.

Without details, it is difficult to assist you. How far did you go in step 4? What error message are you getting?

Hi, I have the same problem. My partitions are 100GB for Vista (C:) and 100GB for XP (X:). After the file copying portion of the XP installation, when the PC restarts, a black screen saying "Error loading Operating System" appears.

I tried several times form scratch but had no success. If I install XP on the first partition it install fine.

Is there a relation with the partition size?

Thanks for helping.

Depa.

This is the error message I get when trying to use the bcdedit.

"an error occurred while attempting to reference the specified entry.
the system cannot find the file specified."

Are you sure you have a complete Vista disc, and not an upgrade disc? Some versions supplied by -i will leave unnamed- companies are not complete install discs and happen to omit more than they should.

Nice guide there, only problem, my computer messed up.
Explanation:
When windows xp installation restarts to finish the installation, it said error loading operating system, like another guy on page 14 on the thread.
So I fixed the vista boot with the command prompt in the install disc, bootrec.exe /fixmbr and /fixboot. BUT! When vista is going to load the screen stays black, nothing. Ctrl+alt+del and it restarts, shows the safe mode or start windows normally menu, and when I choose safe mode it loads drivers and stay there like it bugged saying please wait, ctrl+alt+del restarts it also.
I need your help! I'm no noob to comps but this is ridiculous.
Also, my windows xp install disc won't even load now, makes the black screen, same bug!
My guess is that vista tries to boot with the X: partition instead of the C:.
But how can I use diskpart to reformat this partition and extend C: to bring it back to normal and repair that stupid boot?

Successfull Dual Boot - An update
 

Great "how-to" William,

Just thought I'd make a quick post that the proceedure works very well. There seem to be a preponderance of posts from those who had, or are still having, problems.

The proceedure was not without hiccups, the bootrec.exe steps failed for me, but an alternative solution was found. Suffice it to say the boot manager DOES need to be fixed for the computer to boot back into Vista and to finally dual boot. There are other posts in this thread that explain how this can be done.

As far as the "full Vista install" dvd that some are asking about - this is needed in William's explaination to fix the boot manager - the notebook that I installed a dual boot on was supplied with a "Windows Anytime Upgrade" dvd. This can be used to perform the "Repair your computer" step 3.

I know that HP and Toshiba do not supply this dvd with their consumer notebooks, I am glad that I purchased a "cheaper" model to do my dual boot!

This is just to encourage those who have tried and failed to get the dual boot to work - it does!!!!! and I am a happy bunny.
Martin

Well I still can't get Vista to load again even with the boot repaired.
Just a black screen after I select boot normally or safe mode (bugs).

Anyway with some messing around I found out that my windows xp somehow decided to install on the wrong partition even though I'm willing to bet my life that I made no errors.
Can someone at least please tell me how to copy an entire folder and its subfolders to another directory? I tried xcopy and robocopy but it seems I get it wrong.

EDIT: Ok I found out robocopy "folder" "destination" /e

Now I'll just have to format and reinstall, ah thank you jesus :icon_neutral:

I backuped my things and I'm trying to reinstall vista, problem after the install, when it reboots it a blinking cursor on a black screen stays there and does nothing (right after the post).
I formatted my drive and did everything I could but VISTA JUST WON'T INSTALL. IT'S DRIVING ME CRAZY I'VE BEEN WASTING MY TIME FOR 2 DAYS!