Windows 7: Dual Boot Installation with Windows 7 and XP

I tried manually removing a drive letter from C: but that didn't work. Gave me the same error as the other day.

So, I used Paragon following the guide here: Moving Win7 Partition to Another Drive by releasing, on the XP partition, the partition of C: (100MB system partition) and then changing the letter drive of E: (actual XP) to C:. Rebooted into XP and it seems to boot fine till it hangs at the XP splash screen. I just reverted back to C: as the 100MB and E: as XP and XP boots fine again, but with the same drive lettering as before. SYSTEM partition is still labeled as drive C:. Also, drive C: went from having 72MB free space to now only having 32MB of free space. When I opened C:\ now it shows a Program Files folder which shouldn't be there...Do I have any other options before I ask and see if I can reinstall XP, or even better, install XP over everything then install Windows 7?
Attached some images to show what I mean.

Thanks for the help.

Yes. You can Boot the XP CD to run an XP Repair Install

Once it repairs and hopefully claims C for XP, follow Steps 13-17 in Method Two of this tutorial to add Windows 7 to the Dual Boot.

If this fails, boot the Windows 7 DVD to mark 100mb partition Active: Partition - Mark as Active (Method Two). Then from DVD Repair console run Startup Repair - Run 3 Separate Times until Windows 7 starts. Install EasyBCD 2.02 to Add XP.

The only other thing that I can think of is to mark XP partition Active before running XP Repair install to try to force repair to write XP System boot files to XP, thereby possibly claiming C. Then boot Windows 7 DVD to mark 100mb Active, Repair Windows 7, add XP using EasyBCD.



If neither of these work you can reinstall using Method One for the easiest Dual Booting method without possible interference by the 100mb SysReserved partition.

You can't successfully change an o/s drive letter after it has been installed.

The paragon app. is for changing it back to it's original installed letter - not for making it something different.

Some kind of reinstall is needed.

Perhaps the repair reinstall Greg mentioned will do it - I am not familiar with XP - so it'a worth a shot.


Might be easier to install the app in question on another machine - track the registry changes - export them and change any letters in the .reg file. as necessary.

IMO, Best to a clean install, with Methed one.

The XP drive letter did not slip or change, Windows XP will always take the 'next available' drive letter for its self during install, it's not smart enough to tell the difference like Windows 7 can.

If there is a SysResv partition in the first position on a HDD/SSD XP will always letter it as C:

XP will not allow the SysResv as C: the "System" partition or the XP drive letter to be changed without HAL errors.

If XP is installed to the first partition as C: it must be left as the "Active, System" partition for the Windows 7 install or you will get HAL errors when next booting to XP.

The only way to get XP installed as C: is to install it to the first physical partition on a HDD/SSD.

Win XP will always make SysResv as C: When Windows 7 is installed first.

You can remark Win Xp to C: the with Paragon app.

But the biggist is problem is HAL errors.

I've just wasted 12 hours following this howto. This is an existing Windows 7 PC. Somehow the XP installation corrupted the Windows 7 partition.

Long ago there was a product called Boot Magic. IIRC it would hide inactive partitions so you could have several windows (or other) installations on different partitions and they could all be drive C: and would not conflict with each others. It doesn't seem like it still exists though?

Basically the object of the exercise is to have a separate partition to use for games for my kid in order to not have my "business" partition messed up by the games. I though having the game partition using XP would make it easier, obviously not so.

I see there's a Windows 7/Vista howto but no Windows 7/Windows 7. Maybe there is no difference?

Essentially I would prefer the two partitions would be completely separated from each others. If VM's weren't so poor for gaming I'd install a VM for it.

Did you use Method one or method two?

If you wont Win XP to be C: & Windows 7 to be C:, you need to use Method one.

As this was an existing Windows 7 PC adding an XP partition I naturally used method 2.

Actually I want them both to be drive C as I explained.

Hello peterpallesen, welcome to Seven Forums!

To be " C: " XP must be the first partition on the HDD or it will be the "next available" drive letter.