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I have just bought an HP laptop with Windows 7 (64 bit). It has a 500 GB HDD with three partitions: a small hidden system partition, a 12 GiB HP recovery partition, and a 450 GiB C: boot partition.

I would like to split this large C: partition into two partitions, leaving only 100 GiB for the system, and giving the rest to a new data partition.

Although the Windows built-in Disk Management utility has an option to shrink the bootable partition, it only allows me to shrink it roughly by half, even though only 20 GiB on the partition is used. As far as I understand, system unmovable files lie in the middle of the partition, preventing Disk Management utility to do what I want.

And since new HP laptops don't come with OS installation disks (they only allow you to create recovery disks yourself), I can't just repartition HDD and then reinstall OS.

So, is there a way to shrink the C: bootable partition and preserve Windows 7 working?

P.S.: I have tried to use the third-party GParted utility, and after shrinking the partition, Windows 7 stopped booting, with a BSoD. System recovery didn't work, and I had to do factory recover. Since this is a long process, I would like to avoid doing it again :) So, please, suggest only proven solutions.

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7 Answers 7

up vote 57 down vote accepted

In the low-level tasks, like working with an HDD system partition, I prefer to use native tools as much as possible, and switch to third-party tools only as a last resort, if none of native tools worked. So, directed by harrymc, I gave Windows Disk Management another try.

I first turned Virtual Memory and System Restore off, removed System Volume Information folders, and after that Disk Management utility allowed me to shrink the C: partition as much as I needed. After that I turned the features back on.

The following instructions may help you to identify what application or component is preventing your partition to shrink. First you need to find the latest event with ID 259 in the Windows event log (see Event Viewer / Windows Logs / Application). The event is generated when the system analyses a partition, and if you have already tried to shrink a partition via right-clicking on it in the disk management snap-in, then the event should be there. Another way to make the system analyze a partition is to run the Windows built-in defragmentation utility. The event tells you the last unmovable file or just the number of the last cluster of such a file. It also tells you the complete command to run from the command line to get more details about the last unmovable file. (Alternatively, you can probably also try to calculate the cluster number as min allowed partition size divided by cluster size, and then run the fsutil command with the appropriate parameters).

The filename will give you a hint to guess, what program or feature is locking your partition. And then you can turn it off or uninstall, and see if it helped. In my case turning off Virtual Memory and System Restore was enough. Sometimes it is also necessary to turn off hibernation, etc. And sometimes partition defragmentation may also help. Also, as stated in the WindowsITPro article, Windows Search Index files and Internet Explorer temporary files can also be "unmovable".

P.S.: Thanks everyone for answers. Probably third-party tools would also work in my case, and probably they are easier to use, but as I have already told, for such kind of tasks I prefer to use native tools as much as possible. Also, personal thanks to harrymc for the important hint.

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I couldn't quite follow the fsutil comments. But after I read a post on shrinking NTFS (…), it became clearer. Don't try fsutil first, attempt a defrag and then look in the Event Viewer Application Log for defrag events (Event ID 259 as noted above). The log message actually gives you the instructions for which fsutil command to run. – icc97 Jun 29 '14 at 14:07
Also have a look at WindowsITPro (…) for hints as to what could prevent shrinking a disk: System Restore, IE temporary files index, Windows Search Index, Pagefile. – Pierre Arnaud Oct 31 '14 at 5:29
@icc97 's comment nails it!!! Using the link s/he shares, I was able to narrow down that the file preventing me from shrinking was a bloody Norton file!!!! Thanks for that link. – Jet Blue Oct 21 at 5:03
@jarno, try to disable the DiagTrack service and reboot the system. – Alex Che Nov 2 at 8:13
It is not necessary to run the defragmentation utility to identify what application or component is preventing your partition to shrink: If you go to the disk management and choose to shrink a partition via right-clicking on the partition, the system analyzes the partition and after that the Defrag event of ID 259 can be found in the log. – jarno Nov 3 at 18:41

First, I would backup the system partition (for example, with Symantec Ghost v11 Enterprise). And for good measure, also image the ENTIRE drive (you can restore much faster than with HP's restore facility).

Then delete the C: drive and create two new partitions to your likings with a partitioning tool of your choice. Then deploy the image of the former C: drive to the first partition.

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This sounds reasonable. Do you think Ghost will cope with unmovable clusters in the way that will not break Windows? – Alex Che Dec 28 '09 at 10:22
I don't believe it will cope with partition size that is less than the original. – harrymc Dec 28 '09 at 14:12
believe me, Ghost WILL cope with target drives that are smaller than the source drive (unless the ammount of data exceeds the available disk space, that is).say, you have a 450 GB partition and 435 GB are free, then you can clone that partition to a 15 GB partition, no problem. – Molly7244 Dec 28 '09 at 14:37
@Molly: As this is the system drive, do you know from experience that Ghost can move these unmovable Windows files? – harrymc Dec 28 '09 at 19:27
yep, cloned a 750 GB drive (single partition + reserved) to a 320 GB drive because i needed the big drive elsewhere, no problem. i'm not using bitlocker though, that would a different story altogether. – Molly7244 Dec 28 '09 at 19:43

If I was you, I would give Gparted another try, it can be used as a Linux boot disk and can resize disks very well.

If you take a look at the download page, there is a warning with a bug relating to NTFS disks so you may want to try a previous version.

WARNING: Recently there have been several reports of problems when resizing file systems using gparted-live-0.5.0-3. In the case of the NTFS file system, The error message seen after the partition is resized is:

  ERROR: Current NTFS volume size is bigger than the device size!

The problem appears to be related to the combination of packages, Linux kernel, and patches used in the GParted Live image. We are investigating to find the root cause of the problem. Until this problem is solved we recommend GParted Live 0.4-6-1 for resizing all file systems.

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he already did that, but GParted didn't go down too well with his system. – Molly7244 Dec 27 '09 at 16:07
... I think that was edited after I wrote this as I didn't see that before. – William Hilsum Dec 27 '09 at 16:29
Yes, I have the very same error. I didn't see this message when I was downloading GParted. Probably the downgrade will help. And no, it was not edited after you wrote this. – Alex Che Dec 28 '09 at 10:36
@Alex, sorry, I must of missed of missed it then, but hopefully this will help. – William Hilsum Dec 28 '09 at 11:33

Some Windows files are unmovable, and are unhelpfully allocated by Windows at the end or middle of the disk, so that one can only shrink C up to a limit. Which is exactly what you have discovered : the disk cannot be further reduced without destroying Windows.

The only solution is to reinstall Windows in a smaller partition. In your case, you will need to delete the existing system partition and divide it into two partitions via a 3rd-party tool, then restore Windows into the first partition on the disk. Do not touch the restore partition!

I suggest using Paragon Partition Manager 2010 Free Edition as having a good user interface. Otherwise you can use any other tool such as GParted.

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Thanks for the answer. But after I'd shrunk the partition with GParted, I was not able to do system restore on it for some reason. The only option I had was to do factory restore, which restored the whole HDD image. I'm afraid that your solution may lead to the same. – Alex Che Dec 28 '09 at 10:29
Yes, it certainly will lead to factory restore, but there's no other solution. I only ever found one partition manager that claimed to be able to move these Windows files, and it also destroyed my disk. The best try you can do is turn off the pagefile and system restore and clear the Recycle bin, defragment your disk so as to consolidate free space, and retry resizing. Please note that the Win7 Disk Manager is as good for resizing as any other product - if it can't do it then no other product will without destroying the disk. – harrymc Dec 28 '09 at 10:52
Thanks, I'll try it. And sorry, my reputation is not enough to upvote your answer. – Alex Che Dec 28 '09 at 11:41

I've been banging my head for several days in an attempt to shrink a Windows 7 primary partition that hosts the OS. The problem was a set of system files located in the middle of the partition that were excluded during the defragmentation process. Various attempts with several disk partitioning programs, some of which touted their ability to relocate all system files, succeeded in creating only more frustration.

The solution:

Turn off System Recovery. The files that would not relocate during defragmentation were created by that utility and contained all the restore points. When you turn off System Recovery, these files are deleted. Once deleted, Windows 7's Disk Management utility was able to shrink my 259GB C: partition to a bit over 40GB.

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Exactly how can System Recovery be turned off? – Peter Mortensen Dec 24 '14 at 8:39
Unfortunately, turning off system restore didn't help me (Win7 x64). – Dženan Feb 9 at 22:32

For a bitlocked drive I have successfully used the tool Raxco Perfect Disk 12 (evaluation version).

It contains a defragmentation tool with a 'shrink drive' profile. It can move many unmovable files on the fly. In my case, I needed to schedule it at boot anyway and it did the job. After that, I was able to shrink the drive from the Disk Management console in a standard way.


  • It worked despite the fact that my system drive was bitlocked. Bitlocker would prevent Linux tools I suppose.
  • It did not upset my bitlocker setup. Some tools that do mess with the boot sequence turn on bitlocker recovery mode.
  • It did not require disabling, uninstalling or removing any files.
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I'm not using bitlocker, but for me this was absolutely the simplest solution, worked perfectly first time on a frewsh install of Windows 7 pro. I used the 30-day evaluation of Raxco PerfectDisk v14 Select Drive Preferences, Default optimisation method to "Prep for Shrink" and it moved the tail fragments such that I could have shrunk the drive down to 42Gb. Thanks. – Ed Randall Jul 30 at 20:33

GParted solved my problem! After struggling with unmovable files in the standard Windows Disk Manager I finally used GParted from the Ubuntu 10.04 (Lucid Lynx) live CD. It worked like a charm!

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Did it have any negative side-effects? – jarno Oct 31 at 18:13
As far as I remember - no. – Laurynas 3 hours ago

protected by DMA57361 Mar 1 '11 at 8:20

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