Skip to main content

Copy Partition operation leads to wrong active/primary partition

Thread needs solution

Using Disk Director (2239), I used right-click to copy my active/primary partition/drive c to a non-allocated space which I specified as NTFS and Primary. This became drive F upon rebooting.

I then ran OS Selector setup so I could boot this partition/OS. The settings for the partitions under properties all seemed right with regard to which would be primary and active and assigned to drive C. Drive F would become drive C and C would be D or F (I can't remember). So far so good.

However, after booting I ran Disk Director again which reported that the active partition was drive F mentioned above but drive C remained assigned to the original partition that I had copied rather than switching the two assignments as I expected.

I tried switching the assignments via disk director so that the active would be drive C instead of F.

Acronis rebooted and presumably finished without an error, but nothing happened to the assigments after the boot. The active remained F but windows presumably loaded off of C (the original partition).

0 Users found this helpful

This happens because you copied the partition and when you try to boot the copy the previous assignments are still in the Registry. As a result, C: gets assigned to the C: partition that was in the original Registry (the source/original partition).

To fix the problem, you need to boot into the original OS (the source), load the SYSTEM Registry hive of the copied partition (F:) and clear the MountedDevices key of assigned values. An example of the procedure can be found here. After you clear it, reboot into the copy (I'm assuming that you have the copied partition set as the Active partition for that boot entry) and Windows will assign C: to the booting (Active) partition.

Another solution is to load the hive and then swap the C: and F: assignments. Basically, you want the C: entry pointing to the copied partition instead of the original. You would rename \DosDevices\C: to \DosDevices\F: and \DosDevices\F: to \DosDevices\C:.

Note: Both of these examples assume that F: is assigned to the copied partition when you're booted into the source OS (the original partition).

If you have any questions about the procedure, feel free to ask.

Why was this not a problem when I restored to the other partion from a backup .... the partition I restored to was still Drive F.

I was able to boot the retsored partition just fine... I think ... as Drive C as active.

I thought the purpose of the OS Selector program was to assign the partitions properly and determine which partition is active or not.... otherwise why include that in the options if it has no meaning. It alsoe fails to explain why Disk Director allowed me to change the drive assignments while that OS was running ... although it didn't seem to actually take place and have affect.

In the past it has always seemed to peform this function when I dual booted before.

I have never "remotely" editied a a registry on another parition ... what file/hive do I want to open ?

OK, I found it ... luckily my registrar registry manager allows me to directly open hive files for editing... will try the boot tomorrow .

The Active partition setting is just a "marker" to let the MBR code know which partition to boot. OSS doesn't make any registry changes. There are many scenarios that can cause drive letter assignment issues. There are also many that don't. There can also be times when everything looks okay and it really isn't. When you boot into a "copied" system, you need to verify in Disk Management that the correct partition is marked as the BOOT, SYSTEM, etc. partition (usually all the same partition if done correctly).

As in the linked instructions, you need to check/edit the settings in the SYSTEM hive on the partition that won't boot. For example: If you can boot into Vista on partition #1 and partition #3 is the one that won't boot properly, you need to boot into Vista on partition #1 and load the SYSTEM hive that's on partition #3.

I don't use DD to make drive letter assignments. I use Disk Management. Also, changing the assigned value for the booting (SYSTEM) partition is not normally allowed. This is why it's easiest to just make the change in the Registry and reboot.

Given that the registry contains the deciding mappings to the physical partition names, then how does a restore to a clean PC or another partition work ? Does the MBR take care of this ?

Howard:

No; the MBR has nothing to do with drive letter mappings. Windows takes care of this - and it sometimes gets it wrong. The above thread is an example of how Windows can get it wrong, or at least have an outcome that is not what you wanted.

So If I try to restore a backup image to my PC if it has been formatted or changed in someway, the restore with the MBR may not give me a bootable windows ?
Sounds like pretty limited restore functionality if that is true.

Howard:

Are you talking about True Image now (restore with MBR...)? This thread was about Disk Director (DD). DD was never intended to be a substitute for an imaging program like True Image.

it's actually about both .... reread my post prior to your first response.

The registry fix did finally work... I had screwed it up by using the open and save defaults which was REG file type ... once I selected to open as hive and save as hive, it worked. :)