The official method to convert dynamic disks back to basic disks is to back up the data, format the disks, and finally restore the data from backup. See Microsoft’s instructions on how to do that here.
Of course, nobody wants to do that, and sometimes it’s not even possible to implement this method. It assumes that you can boot up the computer or at least access the drives and back up the data in the first place. So what are the other options?
Well, I unfortunately had to look for another solution last week when my computer refused to recognize any of my 4 dynamic hard drives. Here are the results of my search:
1. Use TestDisk. If you want to know why and how, keep reading or jump to the conclusion section.
2. If you are lucky enough to be able to boot, follow Microsoft’s own instructions to avoid the backup/format/restore method.
Note: Ignore the title of this knowledge base article and go straight to the WORKAROUND section.
Detailed instructions with screen shots can be found on thelazyadmin.com blog.
3. If your computer won’t boot, read on.
After installing the free VMWare server 1.0.2 and loading Vista Ultimate Edition as a virtual machine on my Windows XP Pro machine, my computer wouldn’t boot in any mode. Last Know Good Configuration didn’t change anything, and a repair install was not an option as neither Setup nor the recovery console were able to detect the Windows installation. Running the map command from the recovery console listed all my drives but they all had question marks instead of the expected drive letters. bootcfg /scan didn’t find anything. ERD Commander couldn’t help either (no Windows installation detected). I wasn’t even able to mount the drives using a Linux live CD.
My next step was to buy an external enclosure for my SATA drives (Vantec NexStar 3, works great) to backup the data from a working computer. When dynamic disks are connected to a computer running XP or Vista, they show up as Foreign in the Disk Management console (diskmgmt.msc). All you have to do is right-click the drive and select Import Foreign Disk. Except this time it didn’t work, and instead I received 2 error messages back to back:
INTERNAL Error - The disk group contains no valid configurations copies (C10000B6)
followed by
Unspecified error (80004005)
Looking up these error messages didn’t lead to anything useful so I decided to give up on the dynamic disk to basic disk conversion topic and started to search for data recovery software. That’s how I found TestDisk.
I ran TestDisk on a XP Pro laptop, it detected my USB-connected “foreign” drive, found all my “partitions” (dynamic disk volumes), allowed me to backup my data to the laptop, and offered the option to write a new partition table based on what it had found. I did just that, securely removed the USB enclosure, plugged it back and voila! My laptop detected a new basic disk, with partitions instead of volumes, drive letters, and best of all, all my data intact.
I was then able to reinstall the drive in my computer, repair Windows and from there run TestDisk on the three remaining drives so I can confirm that it works for external (USB) drives, IDE drives and SATA drives.
Conclusion:
TestDisk 6.6 will allow to backup your data and, if you let it rewrite the partition stucture, it will convert your dynamic disk to a basic disk without touching the data.
Run TestDisk:
Select Create to log information.
The program detects all the drives connected to your computer (internal, external, Flash drives).
Highlight the one you want to work on, select Proceed and press Enter.
Make the appropriate choice for your computer and press Enter.
Select Analyse and press Enter.
It displays the current structure. Select Backup first, then Proceed. Backing up first is a good idea if you later want to restore the drive’s partition structure.
It might take a while to get to that screen if your drive is having problems, but eventually, it’ll display all the partitions it found. Select a partition and press P if you want to see the files stored on that particular partition, then press c to copy the files to the folder TestDisk is running from any available drive with enough free space. [Thanks to commenter Bob Janes for pointing out to me that it is indeed possible to backup your data anywhere you wish]
Press Enter to continue.
This is where you can make the dynamic to basic drive conversion happen. Select Write, then press Y to confirm that you want to write the new partition structure to disk.
Quit the program, reboot the drive you just modified and enjoy your new basic drive.
43 responses so far ↓
Ulysses // May 9, 2007 at 4:55 pm
Thank you very much, especially for the screenshots at the bottom.
By the way, the above post smells slightly spammy.
mypkb // May 10, 2007 at 4:28 am
I’m glad you find this post useful, it motivates me to keep posting.
You were right about the other “comment”, I deleted it.
Turbo Donkey // May 11, 2007 at 9:00 am
That it the shizzle, just used it to save my ass… downgrade to basic works perfectly! even after I cloned the damaged dynamic disk to another one!!
PDy // August 20, 2007 at 3:08 pm
Good it is work perfet. Thank you for help.
Jacob wikman // August 21, 2007 at 3:28 pm
Great stuff! This guide saved my bacon!
James O'Connor // August 23, 2007 at 5:02 am
The c (copy) function only works with NTFS (not FAT)-formatted disks. Mmm, looks I’ll have to look for another way to backup my defunct external disc….
Any suggestion?
Chris M // September 7, 2007 at 4:43 am
This is what I love about the Internet. A good programmer gives away a nice tool like TestDisk, and then someone else shares their experience using that tool.
I just installed Vista to a new SATA disk and added another PATA disk from my previous WinXP system and came across the “cannot convert dynamic disk” issue.
20 minutes later it’s fixed. A quick Internet search, fantastic instructions for just the solution I’m looking for, a free tool, and voila, I’ve got all my old data.
Thank you very much, mypkb.
Bob Janes // September 8, 2007 at 11:40 am
Thanks for this - looks like it’s saving my bacon. I have a couple of big NTFS discs that are suddenly showing up as dynamic after a PC rebuild. Trying to recover both partitions on the first of them shows Bad Structure but I am able to copy the files to another drive.
BTW: you do need to have enough free space for a file copy but you don’t need to run TestDisk from that drive. It is possible to navigate the folder tree to another drive using the cursor keys.
Thanks again, Bob
mypkb // September 10, 2007 at 5:07 am
@Bob Janes
Thank you very much for pointing that out. I edited the post accordingly.
spider // September 15, 2007 at 6:46 pm
I got the same problem.accidentally i converted my 80 gb hdd to dynamic and deleted a partition while trying to recover back to hdd.I tried almost all the softwares(near about 25) available on net.I tried this article too but test disk gave me wrong information that on my dynamic disk have 5 partitions although i have 7 on basic disk that were converted into dynamic disk.
I found only 3 softwares identifying correct partition 1st power data recovery (http://www.eofsoft.com) and Paragon Hard Disk Manager, version 8.5.(Even paragon says that its able to convert dynamic to basic but in my case it was not able but it shown all files and folders in each partition through volume explorer option and i recovered files safely by both softwares).3rd software was r studio.
some other best links i found were
http://thelazyadmin.com/blogs/thelazyadmin/archive/2007/01/17/Converting-Dynamic-Disks-Back-to-Basic-Disks.aspx
http://www.wilderssecurity.com/showthread.php?t=102958&highlight=dynamic+disk
acronis also claims but it dint recognized my dynamic partitions.Only one software left to which i will try in night that is Acronis True Image 9.1.
I spent whole day for this work so friends save ur time by my hard work.I will say thanks to the writer of this nice article which inspired me to write my experience.if any one has other experience do wrte to help other people as time is damm valuable :-))
spider // September 17, 2007 at 2:52 pm
hi frns me again,there’s one more software that works nicely it mounts all partitions in the dynamic disk its name is Find and Mount.It loads all partitions like basic disc partitions after selecting one by one.
:-)).m downloading Acronis True Image 9.1 and will update u all
Taylor // September 24, 2007 at 8:14 pm
Production w2k3 server: Worked perfectly! and on the system disk no less.
Jules // September 25, 2007 at 10:48 am
Worked like a charm on vista. big big thanks.
Frank Caputo // September 28, 2007 at 3:36 am
Worked perfectly for me, and saved me 1+ days of reinstalling. Thank you!
Khalil U // September 29, 2007 at 8:02 am
Works like a f****** dream, its amazing how simple it really was. Plugged in the dynamic drive to an external enclosure, ran the program, followed the screen shots, works like a charm. If you do it properly, you don’t have to copy your information over; once its converted back to a basic disk, your info will still be there
Stunning. Simply stunning.
Khalil U // September 29, 2007 at 8:59 am
Just used it again on another HDD. This program is sexy. I thank you, my good man, for putting this together.
Rob Garsia // October 1, 2007 at 11:49 pm
I had a sbs2003 server - upgrade version. Got it booting of the drive ok after a hdd fail. I then thought that I should get a software mirror as the cheap ass raid controller would not create a mirror from an existing disk!!! So I merrily went about converting the disk to dynamic - oh crap the system wont boot and the conversion failed. After a little more reading I assume it is because the client was running an upgrade (which the previous support company applied in the great wisdom to save the client some labour - waannnnkkkeeers)and this is a multi OS boot (I think) and you cannot convert a multi os partition. I am currently copying the data using the data copy facility. I will let you know the result.
- but I am confident
Cheers Rob
Matt Macknak // October 6, 2007 at 1:31 am
Bought a new 320gb external USB drive for backing up my work & home pcs. It arrived configured as dynamic drive. Rather than convert my other systems to dynamic drives I wanted to convert the new one back to a basic drive. Microsoft’s knowledge base assumes the drive began it’s life as a basic drive so the instructions posted would not work for me.
The TestDisk utility worked exactly as advertised and in about 5 minutes I’ve got exactly what I need….thanks, so much !
Evan Jacobs // October 26, 2007 at 5:02 am
even though i was able to use data recovery software to back my data up, i tried this method to convert my disk. Lo and behold, it worked beautifully. Cheers!! Thanks a lot!!
Avsky // November 1, 2007 at 5:16 am
Wow, this is the 4th time i’ve come across this problem, and have somehow magically gotten it to work but this is by FAR the easiest solution.
Thank you (:
Can dynamic disk be converted to basic disk? - Page 2 - TechEnclave // November 10, 2007 at 12:57 pm
[...] loss. Let me just search for the software - it was an open source disk management tool. Found it!! How to non-destructively convert dynamic disks to basic disks « My PKB TestDisk - CGSecurity Raghu. Now os boots (after 45mins) if the 500gb hdd is attached, but [...]
Geoff Hibbert // November 17, 2007 at 8:26 pm
I have just received a new laptop. It has a single HDD with XP installed. The drive is dynamic and I want to create second partition for my own data. But unfortunately there is no unallocated space, and Partition Magic and similar are unable to resize the partition (presumably because the drive is dynamic). Can I use TestDisk to convert the drive back to basic without losing my XP install (I don’t have facility to mount the drive in another machine while I do this).
Any ideas anyone?
Thanks.
Isaac // November 26, 2007 at 11:37 pm
This guide is… excellent. You are made of win. EPIC WIN.
Steve // November 29, 2007 at 3:11 am
Thanks man, this worked very well. I will never, ever format to dynamic disk again, not worth it.
Craig // December 6, 2007 at 1:13 pm
Thanks! I looked for quite a while to find a way to read this disk in a USB enclosure on my MAC, and this did it. I was scared and unsure to hit the button, but it worked great with no trouble.
gabez // December 18, 2007 at 5:42 am
when my 1TB dynamic hd was not recognized in my XP Pro fresh install
i was scared then angry then started to panic
the thing was almost full, my heart sank
YOU HELPED RESURRECT MY DRIVE
i thank you from the bottom of my heart
misty // December 22, 2007 at 1:59 am
Hi,
I’ve lost my D partition. XP Setup or Fdisk can not see it. But Dos 6.2 boot disk can see both C and D drives.
testdisk shows the following media:
Disk /dev/sda - 80 GB /74 GiB
Drive D” - 520 MB / 496 MiB
There is this message for D partition:
“Partition sector doesn’t have the endmar 0xAA55″
If I search deeper for partitions, it found three of them, which is correct according to earlier healthy partitions: 1. C partition, 2. D partition 3. 7MB partition for XP OS use.
* HPFS-NTFS 0
D HPFS-NTFS 1
D HPFS-NTFS 732
I get “Bad Structure” error if I choose any options other than D-delete for the 2nd and 3rd item.
Is there any hope in fixing my D drive? How can I fix it. Thanks.
Alex // January 20, 2008 at 7:10 pm
Thank you, you saved my day!
Palmar // January 25, 2008 at 4:46 pm
Thanks for the article! Helped me a lot!!!
Worked perfectly
Abhi // January 28, 2008 at 5:28 am
Hi,
If I choose to write the partition table without saving the data, would it still remove the data as it converts the disk into ‘basic’ ? I need to know this as I dont have a storage to copy the 200 GB of data somewhere else before converting to basic.
Kindly let me know.
Thanks for help,
-Abhi
mypkb // January 28, 2008 at 6:27 am
@Abhi
You do not have to back up the data first.
The method described allows you to convert a dynamic disk to basic without losing data. I chose to back up first “just in case” something bad happened. So it’s up to you.
Abhi // January 29, 2008 at 4:27 am
Thanks pkb. Now, I had two partitions in the disk earlier (when dynamic).
I ran Testdisk on one partition (smaller size one) and converted the disk to basic. It shows very well on Disk Management as basic disk and that volume comes up in explorer as well.
For the other partition (which is the main big one), it now appears as ‘unallocated’ in disk management.
I think I need to run testdisk again on it as well now, right ? Also, when I run it, what should I mark this partition as , P or * (primary or primary bootable). It currently appears as D.
Am sorry if this is a very trivial question !!!
System Zero - Web Developers » Archive » How to change your sata drive from Dynamic to Basic in Windows Vista // January 29, 2008 at 3:33 pm
[...] and not only that, it’s free!!!. I came across this solution in an article called ‘How to non-destructively convert dynamic disks to basic disks‘. If you have the same problem as me then I would encourage you to follow the steps in that [...]
Trefor Brock // February 5, 2008 at 10:16 am
thank you. with the disk set as dynamic I was unable to have a dual boot scenario with linux. this quickly and safely solved the problem….in 2 minutes.
Brewer Shettles // February 8, 2008 at 10:47 am
Thank you!!! Partitioned my drives back to basic. Worked as described. Read / followed the Screenshot directions. Excellent results!!!!!
AlanC // March 14, 2008 at 1:58 pm
Thank you so much for posting this. Why can’t Microsoft make it this easy?
Tc // March 16, 2008 at 12:24 pm
Wow, this works perfectly! Managed to convert my dynamic disk to basic disk very quickly. Thanks for recommendig it and for documenting the steps!
Hello71 // March 20, 2008 at 2:39 am
Why the hell does Microsoft leave this feature in Windows XP and Vista anyways? It’s not supported. Anyways, saved my (very large) bacon. Thanks for putting this together.
John Warden // April 4, 2008 at 3:26 pm
Wow!! Pure win and awesome!! You are my hero, mate! This worked like a charm and saved my a$$.
Mukund // April 22, 2008 at 8:20 am
I have a problem. I ran this utility on W2K3EE dynamic disk. After that, server restarted and it gives error “security manager could not be initialised”. This is a critical server and somebody please help in fixing this problem.
Jason L // April 25, 2008 at 9:53 pm
Ran this on a Win2k server to that had 2 logical partitions: Boot and Data. The goal was that I would be able to use the free space to extend the boot partition. I used testdisk to delete the data partition. I assume that is deleted correctly, However, when I boot it appears to boot normally, but upon attempting to login, it immediately logs me back off and I’m placed back at the login screen. Any ideas anyone?
Melted // May 2, 2008 at 1:43 am
Hey, man, you’ve just MADE MY DAY!
Thank you very much, now I finally can see my old 250 Gb Barracuda HDD from good old Win XP in that crappy Vista Home Premiun - without digging disk structure, and all that odd hex-editing of disk partition table.
THANK YOU!
It just WORKS!
Shonsu // May 7, 2008 at 11:47 am
I’ve been having issues with a 500gb SATA II drive that I setup as dynamic. I’ve searched for ways to convert it back to basic. I tested this in VMWare — worked great. Bit the bullet and did it live on my drive and in about 5-10 minutes I was back to basic disk and also resolved some other software issues (totally unrelated to dynamic disk…of course!). Awesome assistance! Thanks for the article.
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