This guide is designed to help you separate an XP and Vista dual-boot setup using Vista's boot manager into two separated (somewhat isolated) installations where each one can boot independently of the other's partition. This is necessary when you want to use a third-party boot manager or you need (or want) to change to isolated installations.
When you use the Windows boot manager, Windows will setup all installations to boot from one partition. This partition is the partition that is marked as Active at the time of the installation. For example: You had XP installed on your computer and you decided to install Vista. Vista installed okay and now you can select between XP and Vista using Vista's boot manager. However, Vista installed all of its boot files onto the XP partition and took over the booting of XP.
Now you want to use a third-party boot manager and you've run into a problem. Perhaps one of your installations won't boot. Perhaps both won't boot. Or, you may be getting the same Vista boot menu for each OS instead of the selection booting directly into the desired OS.
An XP installation CD that will allow you to enter XP's Recovery Console.
A standard Vista DVD that will let you enter Vista's Repair section and run the Command Prompt.
Here is an overview of what the system looks like when setup to dual-boot XP and Vista using Vista's boot manager.
When the computer boots, you are presented with a menu from which you can select which OS you want to boot. Usually, there will be a time-out value that will count down and boot the default OS if you don't make a selection.
If you open up Disk Management in XP and look at your drives, you'll notice that the XP partition is marked as the (System) partition (the booting partition) and is assigned the C: drive letter. The Vista partition is visible and assigned the next available drive letter (in this case, E:).
If you open up Disk Management in Vista and look at your drives, you'll notice that the Vista partition is assigned the C: drive letter and that the XP partition is assigned the next drive letter as set during the installation (in this case, D:).
The important thing to note here is that the (System) partition is still the XP partition. Vista is booting from XP's partition.
As is normal when booting using this method, Windows can see all other Windows partitions. Vista can access the XP partition and XP can access the Vista partition.
In order to view the booting files, you need to enable viewing of Hidden and System files and folders.
In Vista, click on the Start button and then on Computer. Click the Organize button and then select the Folder and Search Options entry.
On the View tab, select the option to Show hidden files and folders and uncheck the Hide protected operating system files (Recommended) option. Click Yes on the warning that pops up.
Here is what you want the options to look like:
Click the OK button to close the Folder Options window.
Now, if you browse to the XP partition and look in the root folder, you'll see Vista's bootmgr file and the Boot folder.
Inside the Boot folder, you'll see the BCD file along with the rest of Vista's boot files.
If Vista UAC is activated (the default), you'll need to open a Command Prompt in Administrator mode in order to run bcdedit.
Click the Start button, then All Programs, then Accessories. Right-click on Command Prompt and select Run as administrator.
Click Continue to allow the program to run.
At the prompt, run the following command:
The output from bcdedit will be displayed. Notice that, as shown by Disk Management, Vista's partition is C:, XP's partition is D: and the booting partition is D:.
For a comparison, here is the output of bcdedit when run from XP:
Boot to the XP CD and select the Repair option.
Select the XP installation (in most cases, this will be the C: option).
If you have a password, enter it.
Run the fixboot command to return the XP partition's Boot Sector back to its original state.
Confirm that you want to write the new Boot Sector:
If you now removed the XP CD and rebooted, the computer should automatically boot directly into XP as it did prior to installing Vista.
Boot from the Vista DVD and follow the steps to get to the Command Prompt.
Select Repair your computer.
On the next screen, it should find your Vista installation. Click the Next button.
Finally, click the Command Prompt option.
Running bcdedit at this point will display the configuration as seen from the Vista DVD's Command Prompt.
The first step is to remove the XP entry from the BCD file. This is accomplished by using the following command:
Running bcdedit again will verify that the XP entry as been removed.
The next step is to change Vista's entry to boot from the Active (booting) partition. To do this, run the following four commands:
The output from bcdedit will show the changes.
Now we need to copy Vista's booting files to the Vista partition.
Make sure both the C: and D: drives are in their root directories.
First, we'll copy the bootmgr file. It's a hidden, system file, so we'll have to unhide it, copy it and then re-hide it. I also recommend you rename the original file on the XP partition instead of deleting it (just in case).
Now, make the Boot folder on the Vista partition and change to it.
Then switch back to the C: drive and change to the Boot folder.
Here is what the procedure looks like:
Next, copy the contents of the Boot folder.
If you switch to the D: drive (the Vista drive) and run the dir command, we can see the new Boot folder. Now we need to hide it and rename the original on the XP partition.
The final step is to make the Vista partition Active and write Vista's Boot Sector code to it. For that, we'll use the Diskpart and Bootrec programs.
Here is what the procedure looks like:
We are done with the Command Prompt so we can close it.
Remove the Vista DVD and click the Restart button. The computer should boot directly into Vista.
Once booted into Vista, a look at Disk Management will show that the XP partition is no longer the (System) (booting) partition. The Vista partition is now the booting partition for Vista.
Now that XP and Vista have been separated, you should be able to install your boot manager with much more flexibility and, hopefully, better success.