How to increase or decrease your Boot Camp partition

If you’re running Mac OS X and Boot Camp you may need to increase or decrease the size of your Microsoft Windows Boot Camp partition, depending on what great videos games are out for Windows at the time. 😉

To accomplish this task without losing all your Windows data you need 3 things.

  1. Mac OS X 10.5 (Leopard)
  2. An HFS+ Mac-formatted external drive
  3. Winclone

To decrease the size of your Windows partition use the following steps.

  1. Make a backup of your Boot Camp partition from Windows. (optional)
  2. Run Winclone.
  3. In the “Tools” drop down click “Shrink Windows (NTFS) file system.”
  4. Follow the onscreen instructions.
  5. Wait… it takes awhile.
  6. In Winclone create an “Image” to your Mac-formatted external hard drive.
  7. Use Boot Camp Assistant to return your drive to a 100% Mac-formatted partition.
  8. Use Boot Camp Assistant to make a new Boot Camp partition larger than the file size of your “shrunk” Windows partition image, but smaller than your original Boot Camp partition size.
  9. When it asks for Windows disk, quit Boot Camp Assistant.
  10. Run Winclone again and “Restore” your Windows image to the new partition.

To increase the size of your Windows partition use the following steps.

  1. Make a backup of your Boot Camp partition from Windows. (optional)
  2. Run Winclone.
  3. In Winclone create an “Image” to your Mac-formatted external hard drive.
  4. Use Boot Camp Assistant to return your drive to a 100% Mac-formatted partition.
  5. Use Boot Camp Assistant to make new Boot Camp partition larger than your original partition size.
  6. When it asks for Windows disk, quit Boot Camp Assistant.
  7. Run Winclone again and “Restore” your Windows image to the new partition.

Kind of a pain, but it’s doable. I’ve altered my Boot Camp partition numerous times using the methods above.

97 thoughts on “How to increase or decrease your Boot Camp partition

  1. Nice! Thanks Dusty – I was thinking about installing Boot Camp again on my MBP when my new 320G 7200 rpm drive arrives this week, so this helps make that decision a bit easier. However, I might still leave most of that new space available for video projects – that stuff takes up TONS of space. Can one ever have too much hard drive space? 🙂

  2. Thanks for the post.
    But if we restore the image with the winclone, it will restore also the orignal size of the partion…
    Is it possible to just mount the image and copy the files?

  3. I am running into the issue that Mig describes.. I have the 30 GB winclone file, but the new partition is 85 GB, but once I restore.. it’s only 30GB again…..

  4. From what I understand from the Winclone readme, if the partition is originally formatted FAT32 you will need to convert it to NTFS in order to expand the partition, otherwise the new partition will automatically resize to the original. Hope that helps!

  5. If the partition is converted to NTFS, then that means that OSX may extract files from that partition but not write to it. I have a shortcut that links me to my XP partition, on my OSX partition. I move files from both partitions frequently.

    If you guys always move files between partitions, then this may not be the best of choices. Otherwise, you can always convert the additional space into a backup partition.

  6. I am a little newer to mac than what your explanation gave, but I do have win xp on my mac with about a 22gb partition and would like to increase but not sure I have ever done these steps:
    1. How to make a backup of the boot camp partition from Windows.? )
    2. this step seems easy enough – Run Winclone.
    3. In Winclone create an “Image” to your Mac-formatted external hard drive. How do I make a formatted external drive? can it be done with a USB external drive?
    4. Use Boot Camp Assistant to return your drive to a 100% Mac-formatted partition. Is this easy enough to understand when I run boot camp?
    5. Use Boot Camp Assistant to make new Boot Camp partition larger than your original partition size. Seems I can do this if I can removemy old partition.
    6. When it asks for Windows disk, quit Boot Camp Assistant.
    Run Winclone again and “Restore” your Windows image to the new partition. How do you formatt an external drive to these requirements, HFS+ Mac-format?
    Sorry but I am just learning.

  7. So I cloned my vista partition and deleted it through bootcamp before realizing I needed to shrink it first. Winclone will let you shrink the imaged partition, but its been going for about 2 hours now…anyone know if this is normal?

  8. This worked like a charm on a Moacbook Pro with a 250GB hard drive – formerly a 10GB partition and increased it to 50GB – originally NTFS and stayed NTFS – thanks

  9. Hi, thanks for this post. The instructions are great! I have a few questions though, that I hope you can help with.

    I also have a partition that was too large on my old machine — 60G partition, and I only used 7G — and now I want to move to a new MBP, and use only 15G for the partition.

    I believe I’ve created an image, and I thin I have successfully shrunk it — in Finder Info, it says that the clone is only 4G which sounds about right to me, given I only used 7G of the partition in the first place — but when I try to restore from Winclone, it says that it is 61G again, and therefore two large for the 15G partition.

    CAN you tell me why this is, and how do I fix it? CAN i fix it?

    Secondly, when I AM ready to install this image to my new partition, can you give me some clarification about how to do that? It says:

    6. When it asks for Windows disk, quit Boot Camp Assistant.
    7. Run Winclone again and “Restore” your Windows image to the new partition.

    Is that it? Will I be required to do anything else?

    And after that, I want to use my Fusion software – how do I get that set up? It was migrated from my old machine – will it operate properly or will i need to do something additional?

    I am new to Winclone, Mac, and Fusion, and all of this, so please, go easy on me!

  10. How do you convert the partition to NTFS so it doesn’t go back the old size when you restore the WINCLONE file?

    1. From Windows Start->Run->type “cmd”

      at commandline type:
      convert c: /fs:NTFS

      For Vista/Win7, just type “cmd” from Search box.

      Choose “Y” to all prompts, then restart back in windows. It will take a few minutes while it is being converted.

  11. HELP!
    I did this and now when I try to boot up Windows XP it hangs just after the boot screen on a Black screen.
    Everything went okay until I tried to boot up windows.
    Instead of using an external hard drive I just put it into a folder.
    Can someone PLEASE HELP!!!

    NTFS
    Microsoft Windows XP Home Edition
    Mac OS 10.5.7
    320 GB, 7200 RPM
    2.66 Ghz
    2 GB DDR3
    2009 imac 20″

  12. I am having a problem with increasing the disk size. Everything works fine until I restore the partition contents from the winclone image. On restore the partition resizes back down to the old 5 gigs again. Any ideas?

  13. Hi again, I just figured the partition resizing problem. You have to deselect the bottom three items in the winclone preferences. There actually is a warning abut this problem in the preference pane but I missed it. All is fine now

  14. I have egg on my face. Actually the re reinstall did not work. The new partition was resized the same as the old one again. It was just reported wrongly. I am giving up and reinstalling Windows from the CD. Luckily I didn’t keep files on the Bootcamp partition.

  15. WinClone is AWESOME!

    Here’s my question. I currently have a FAT32 partition with Windows XP (boot camp). I want to double the size of that partition.

    From what I’ve read, I’ll need to change the partition to NTFS (easy enough, using your instructions).

    However, how does this work when restoring a WinClone image that was FAT32? Can you restore this to a newly partitioned NTFS?

  16. can i still do this without putting the winclone backup on an external?

    as in restore it from my internal mac drive rather than external, because my external is formatted to fat32 and wont hold a backup image.

  17. Worked great on Snow Leopard, thanks !!

    I didn’t need an external drive at all, just saved the Image within the Mac partition, no problem!

    and all this without restarting!

    better than camptune I reckon.

  18. hey I did everything but when i go to re-partition my mac itr won’t let me saying that files cannot be moved…

    Back up the disk and use Disk Utility to format it as a single Mac OS Extended (Journaled) volume. Restore your information to the disk and try using Boot Camp Assistant again.

    …I am using Snow Leopard and have not saved the image to an external harddrive, just my documents.

    please help…

    Thx.

  19. Hi Katz, I ran into the same problem before.

    What I did I backup my entire HD using Time Machine and then erased the partition. Then I used Time Machine to restore my backup. After which, I was able to run boot camp again properly.

    Hope this helps. 🙂

  20. Thanks a million for this article! It took around 1 1/2 hours to increase my windows 7 bootcamp partion from 32 to 200GB! No problems.

  21. I’m getting a problem, I made a 32 GB partition and I am trying to restore a 16.86 GB clone, but it lists Boot Camp as 16.85 GB….what’s happening?

  22. Ignore that last post, I have successfully mad a 32 GB partition and is shows up on my desktop, but whenever I try to clone it an error pops up and tells me to check the log. On top of that the partition that I just created disappears from both the desktop and the Finder.

    What’s wrong here?

  23. I got this as an error in the log and I have no idea how to fix it. =\
    ERROR: Filesystem check failed! Windows wasn’t shutdown properly or inconsistent
    filesystem. Please run chkdsk /f on Windows then reboot it TWICE.
    return value of “/Library/NTFSProgs/ntfsclone” –rescue -f -f -f -O “/dev/disk0s3” /dev/disk4 1>&2 is 256

    “/Library/NTFSProgs/ntfsclone” –rescue -f -f -f -O “/dev/disk0s3” /dev/disk4 1>&2 did not complete successfully
    cleaning up: Mounting Disk
    Volume BOOTCAMP on /dev/disk0s3 mounted
    Fri Mar 5 20:42:49 EST 2010

  24. Hey I really want to do this but I’m kind of a newbie when it comes to computers so there were a few things I didn’t understand, what’s a Winclone “Image”, what does it mean to return my mac to a “100% Mac-formatted partition.” Overall, can someone just explain the step to me in a way that’s more easy for someone who knows nothing about computers to understand?

  25. would it be possible to resize the partition using software like EASEUS Partition Master? which runs off the windows section of your drive?

  26. Doesn’t work for me, every time it resizes my partition back to the original size even though I enlarged it and I made sure the last checkbox in Prefs is UNCHECKED.

  27. This solution worked for me. After using winclone to backup my existing bootcamp partition when, I deleted the partition it would not let me create volume of bigger or same size so, I inserted OSX dvd and ran install after that it allowed me to create bigger size volume for boot camp. This took way longer then I thought because of all resize issues.

    Winclone works great.

  28. I wish to decrease size of Boot Camp partition, however I have installed Parallels Desktop 5 virtualization program. Should I remove Parallels 5 before I attempt to use Winclone to decrease the partition containing Windows XP?

  29. I have BootCamp on my Mac 10.4.6 (Panther), and need to add to my Windows partition. Since Mac no longer supports this version, I am stuck with zero disk space. Also i used the FAT file instead of NTFS. I have removed everything but the Windows operating system, so there is not enough memory to defragment, or do anything at all. Any suggestions, please?

  30. Brilliant Tutorial – Worked First time without even having to do a restart!
    Fabulous!

    One little note though, for those who are having issues with the partition resizing itself after restore: Look in Preferences and make sure that “ASR instead of ntfsclone to restore compressed dmgs” is NOT selected.

  31. cheers! thought i would only use windows 7 occasionally but i am using it more than i expected and am quickly running out of HD space. super helpful post. i love the internetz.

  32. Thanks a lot for these instructions. I just want to add one thing to help those who’ll be following these steps in future.

    Make sure that your Windows installation is NOT in the “HIBERNATE” or “STANDBY” mode before you take the backup using Winclone. I made this fatal mistake and could not restore from the backup. It restored the image, but failed at the point of mounting /dev/disk0s3. I checked the log file to find that it failed because Windows was in Hibernate mode.

    Shutdown Windows completely before running Winclone to make the image.

  33. wish i had read all the comments before i started the process…. Sigh. That whole NTFS FAT conversion thing is important.

    Off to start again.

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