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Windows 7: Accidentally Deleted system partition. Cannot boot. Dynamic Drives.

04 May 2012   #1

Windows 7 Ultimate x64
Accidentally Deleted system partition. Cannot boot. Dynamic Drives.

I have a 1.5TB HD of which I originally created 3 partitions of around 500GB each (C, D, and E). I have Drive C: which is my main Windows 7 Ultimate x64 partition. I had an older installation of Windows 7 Ultimate x64 residing on Drive D:. I simply use Drive E: as storage of large media like movies, software, music, or anything else and it does not have an operating system installed.

Yesterday I decided it was time to format my old Windows installation on Drive D: hoping to merge it with my storage drive E: Big mistake, because it turned out Drive D: was my system partition. When my computer tried rebooting after completing the format I got a hang while the post screen says "Loading Operating System..." indefinitely. I initially panicked and tried to re-install windows 7 with my install DVD back onto Drive D: and it still wouldn't boot.

That's when I found a few promising discussions on this forum that gave me hope; mainly starting on the third page of this following thread between user rogerfour and the always helpful gregrocker: Changing the System Partition?

As Gregrocker suggests, I downloaded and burned a bootable image of Partition Wizard. Unfortunately, my entire disk and all the partitions are listed as Dynamic Disk instead of Basic. When I try and do anything inside Partition Wizard it gives an error popup saying it does not support Dynamic Disks in the free version! (╯□)╯︵ ┻━┻

-So then I booted using my windows 7 DVD into installer>repair my computer
I then went into command prompt and ran DISKPART commands to make sure the C: partition was set to active. I also made sure to check the other partitions to make sure they were inactive using "select partition #" and "detail partition." Both D: and E: partitions are listed as inactive. There was also a small 31KB partition doesn't show up when I "list volume." Anyways, it was also inactive.

-I then ran Startup Repair the suggested 3 times (and more), always with a restart in between repairs. At first it seemed to be finding and fixing things, but now it always says "Startup Repair could not detect a problem." Opening the list of diagnostics always shows that the tests complete successfully with no errors.

-I also tried re-entering command prompt and running some other commands suggested by Gregrocker:
"bootrec.exe /fixboot"
Returns: "The volume does not contain a recognized file system. Please make sure that all required file system drivers are loaded and that the volume is not corrupted."
"bootrec.exe /fixmbr"
Returns: "The operation completed successfully."
Bootsect.exe /nt60 all /force
Returns: "Successfully updated NTFS filesystem bootcode" for both C: and D: partitions. It then says "Bootcode was successfully updated on all targeted volumes."

That's about the full extent of what I've tried so far, and I still can't boot. I've tried repairing the D: partition as well, using all of the same steps. The same problems persist. The only difference I have noticed is that I get a slightly different error durring start-up depending on which partition I have listed as active.

If C: is active I get:
"Loading Operating System...
A disk read error occurred
Pres Ctrl+Alt+Del to restart"

But if D: is active I just get:
"Loading Operating System..."

Any help or advice would be greatly appreciated on how to get out of this pickle. I've run out of ideas and most forums suggest I do the things I've listed already, some with slight variations. Is my disk being Dynamic have something to do with the problem? Anyways, I look forward to hearing back.

My System SpecsSystem Spec
04 May 2012   #2

Microsoft Community Contributor Award Recipient

Windows 7 Home Premium SP1, 64-bit

Dynamic disks are pretty much to be avoided at all costs. It usually happens when a user tries to make a 4th partition. A warning should come up asking if you want to convert to dynamic. The correct answer should be "no!!!!!".

Is your data backed up?

You probably have to convert dynamic back to basic. It's doable and there may be a tutorial on this forum about it--if not, there are instructions on the net if you google.

It isn't pretty and your data is at some risk if not backed up.

Are you using version 4.2 of Partition Wizard?

Greg should see this and can give you more details.
My System SpecsSystem Spec
04 May 2012   #3

Windows 7 Ultimate x64

I'm not sure how the Dynamic disk was obtained, it must have been something I did ages ago and never thought twice about.

The data on the D: partition I don't need, want, or care about (hence the reason I decided to format it). Are there ways to convert specific partitions back to basic or do I have to do it for the whole disk? In any case, my whole D: partition is available for whatever kinds of experiments to try and get Windows to boot.

The data on C: and E: partitions I care about but I don't have backed up (I've been meaning to purchase a huge external HD that could handle that task.) I believe I could take the HD, plug it into another computer, mount it, and pull my precious data off before I undergo any extreme "dynamic->basic" conversion. I'd rather not have to deal with that mess though, so I'm crossing my fingers that Greg or someone has some awesome advice or ideas on how get this puppy booting again.

Edit* I just had to check the latest version of Partition Wizard and it's currently in Version 7.1. I got it from the following website:
My System SpecsSystem Spec

04 May 2012   #4

Microsoft Community Contributor Award Recipient

Windows 7 Home Premium SP1, 64-bit

Greg may tell you to get version 4.2 of PW. It has a feature or two not found in later versions, but I'm not sure if it is critical in your case.

Here is a tutorial on converting dynamic to basic:

Convert a Dynamic Disk to a Basic Disk

Among other things, it says this:

Converting the dynamic disk back to a basic disk requires that all dynamic volumes are deleted on the disk first.

Note that there are several methods.

I'd just study that and maybe make a tentative plan, but wait for Greg's input in this thread.

There may be a solution short of conversion, I'm not sure---but in the future you need to refuse dynamic disks whenever possible.
My System SpecsSystem Spec
04 May 2012   #5

Windows 7 Ultimate x64

Thanks, I'll keep that in mind and stick to Basic disks from now until the future.

Also, I found this post: How to non-destructively convert dynamic disks to basic disks | My PKB
...which seems to have some promising results using a program called TestDisk to not only backup my dynamic volumes but also possibly non-destructively converting back to a Basic drive.

I have to go to bed and work in the morning. When I get back tomorrow evening I'll look forward to starting my weekend off with some serious troubleshooting.
My System SpecsSystem Spec
04 May 2012   #6
Microsoft MVP


Download ISO, use Windows Image Burner or ImgBurn to burnto CD.

Boot PW 4.2 CD, click on the Dynamic HD to highlight it, from Disk tab select Convert to Basic disk, Apply.

Normally you are warned a disk is about to convert when you try to create more than four Primary partitions. If this is the case, you will have to first delete the partition that was created causing the conversion or it will not convert.

If you have any problems post back a camera snap of the PW disk map and listings for more help: Screenshots and Files - Upload and Post in Seven Forums - Windows 7 Forums

Once converted confirm the Win7 partition is a Primary partition - if not you'll need to rightclick to Modify>Convert to Primary, click OK.

Next rightclick on the Win7 primary partition to Modify>Set to Active, OK.

Then click on the Win7 HD again to highlight it, from Disk tab select Rebuild MBR, Apply all steps.

If this fails to start Win7, boot into Win7 DVD or System Repair Disk to run Startup Repair - Run 3 Separate Times until Win7 partition holds the System Active flags and boots on its own.
My System SpecsSystem Spec
04 May 2012   #7

Windows 7 Ultimate x64


I successfully downloaded the specific PW 4.2 .zip you suggested and burned the ISO image onto a CD.

However, when I boot from it everything appears to go fine until right after I set the display resolution. A brief splash screen for PW comes up and then I get an error which says "This bootable CD does not Support Windows Server."

I've tried multiple times and keep getting the same error. I also tried the second "boot from Partition Wizard Boot Disc (Safe Mode)" with the same issue.

This seems really weird, I've never had a Windows Server OS installed on my machine ever. The newer PW that I burned seemed to open up just fine :/
My System SpecsSystem Spec
04 May 2012   #8

Windows 7 Professional x64 Service Pack 1

Don't use third party partitioners to partition a drive. Always use the Windows built in one. Microsoft knwos the filesystem of Windows WAY bettery than any third party.
My System SpecsSystem Spec
04 May 2012   #9

Windows 7 Ultimate x64

Oh awesome, I was goofing around googling that error looking for some advice and found something that suggested I go into the Integrated Peripherals in my BIOS and set PCH SATA Control Mode to "AHCI." Also further down in the screen is the option "eSATA Ctrl Mode" which I also set to "AHCI"

When I tried booting into PW 4.2 again it worked! I'm now going to attempt converting the Dynamic Disk to a Basic Disk. Wish me luck.
My System SpecsSystem Spec
04 May 2012   #10
Microsoft MVP


Follow these steps:
How to convert dynamic disk to basic disk with Partition Wizard?

If not can you slave the HD to another computer to which you install Home version of partition wizard 4.2 - Windows Live? If so you can also in that case use the latest free version of Easeus.

Keep us posted. I'll be checking in.
My System SpecsSystem Spec

 Accidentally Deleted system partition. Cannot boot. Dynamic Drives.

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