Resize Bootcamp Win7 Partition - How To

Discussion in 'Windows, Linux & Others on the Mac' started by vesposit, Mar 20, 2012.

  1. vesposit, Mar 20, 2012
    Last edited: Apr 5, 2012

    vesposit macrumors newbie

    Mar 20, 2012
    UPDATE to this thread 4/5/12:
    -just a couple updates to this thread:
    Note that I don't use the MAC side at all.. very rare to go to Mac OS, but it all runs fine.
    -note when in MAC OS I can see the bootcamp partition but not get to the win7 files
    -i can get to files on external drive formatted FAT32
    -there is utility software to allow getting to NTFS Win7 files from Mac but I don't bother
    -below MAC2 just refers to my PC in office...
    -I can get to all the MAC files from the Win7 OS when running fine.

    This is method I recently used to resize my Bootcamp partition running Win7 64 bit so that it woud be bigger. I reduced the size of Mac partition by 50g and increased the Win7 Bootcamp by 50g.
    This was done without having to re-install Windows or re-create the bootcamp part.

    *** feel free to email me with Questions

    *** Brief instructions:
    1. create a Backup image of the Bootcamp Win7 partition (400gig in size)
    -used Winclone 3.0 - this took about 8hrs to run
    - get this application $19.95 (used it many times and works great)
    -created the backup image on a WD passport usb drive with 400g Mac HPFS partition on it
    -this does NOT have to be done - but of course recommended
    -also I have a simple backup of all files on cloud server using "CrashPlan"
    -also I have a simple backup of all files on local computer harddrive
    - with this image you could also load your bootcamp partition to a new Macbook if needed and not have to re-install windows and all aplications...
    - note that Winclone also has instructions on re-sizing the partitions and this method works - but it requires you to destroy the Win7 bootcamp and reinstall using the image, this is fine but takes much longer,
    - so use Winclone to create a image and in worst case you can use this image to restore your Win7 partition, but you should not need it ....

    2. In Mac OS using Disk Utility I was able to simply Shrink the Mac OS partition down by about 50g - this took about 15min to complete - of course you must have 50g of unused space in the partition to shrink it up.
    -it did show a warning that there is a Bootcamp partition and this may be damaged - but that is ONLY if you mess with that partition, by changing size of the MAC partition, does NOT mess with or hurt the Bootcamp partition
    -so here I reduced the size of Mac partition no problem
    -in here I did NOT mess with the Bootcamp partition
    -if you change the Bootcamp partition in here you will lose your Win7 and have to reinstall from a image or scratch

    3. In Win7 64bit OS
    - download free application "MiniTool Partition Wizard Home Edition v7.1"
    -using this I selected the Bootcamp partition - resized - increased to take the 50g of "unallocated space" to the left of Bootcamp part.
    -selected apply
    -this has to reboot and run it's application on boot up
    -this took about 10min to run on reboot

    4. Now in Win7 OS and Bootcamp partition is 50g bigger, now about 450g.
    -ran chkdisk to be sure all is ok - this took about 10min and all was fine

    ***** More Detailed description of the above ****

    ***** 03/19/12 working on Mac2 made new backup of Win7 partition and resized to get more space *****
    -when done BootCamp partition is now 420gig in size
    -also now have backup of Win7 image on WD USB drive "Mac2Win7-WinClone031912.winclone"

    1. installed / run new version of WinClone 3.0
    -run Win7 Chk Disk
    -restart Mac2 - hold Option key - boot to Mac OS
    -downloaded from 19.95
    -I downloaded in Win7 and burned to a CD
    -have to make sure installed as a Application - when first comes up with install screen have to drag the Winclone app icon
    over to the Application icon in the application screen - kind of a visual install dialog box on screen
    -now the app should be in the Finder - File finder - Applicaitons - listed here and started here
    -don't want to run from a CD...
    -I had tried to run from CD but it would refuse to work because of security errors and running from a write protected media
    -so once I copied from CD to Desktop and ran the install dialog to applications it was OK, but has to be installed, not just copied
    or run from desktop or CD - this is just the install program dialog box
    -connected WD external Hdd Passport to USB port
    -first had to use Mac Disk utitity to create a Mac HPFS partition on the usb drive, this is needed to save the image to
    -Applications - Utilities - Disk Utility - selected the USB drive - used partition tool to resize and divide the drive to 375g Mac, 375g Win
    -now can save the BootCamp Win7 image to the Mac HPFS partition with WinClone
    -ran WinClone to make a clone backup of Win7 BootCamp partition
    -was saved to WD USB drive "Mac2Win7-WinClone031912.winclone"
    -this took about 10hrs to run (400gig+)

    --- I tried to use CampTune X to resize partitions - it ran all night and just locked up, tried twice not work as needed

    2. Shrink size of Mac partition from 100gig down to 50gig
    -boot to Mac OS
    -Applications - Utilities - Disk Utility - select top drive - partition - resize
    -Select the Mac Partition - Shrink - type in new size 50gig - apply
    -did see warning about the Bootcamp partition but we NOT mess with this here at all
    -Now Mac partition is smaller leaving empty "unallocated" space between the Mac and BootCamp Win7 partitions

    3. Increase size of BootCamp Win7 partition to use "unallocated space"
    -boot to Win7
    -downloaded Free copy of MiniTool Partition Wizard Home Edition v7.1
    -this version is free from
    -once installed - run Partition Wizard
    -selected the BootCamp partition - Resize - drag slider to left to get ALL now Unallocated space
    -then OK
    -now go to upper right and click Apply
    -it had to restart the Computer - and then did the resize on boot up ins it's own app running before win7 boot
    -this took about 10 min to run
    -now booted to Win7 and all is ok - Win7 partition is increased in size

    4. Ran ChkDisk on partition to be sure all ok
    -Control Panel - Admin tools - Computer Mgmt - Disk Mgmt - Rt clk Select partition - Properties - Tools - Error Chking Check Now
    -it will schedule a chkdisk on reboot
    -reboot system
    -Chk Disk runs on boot - takes about 10 min - all was OK
  2. balamw Moderator


    Staff Member

    Aug 16, 2005
    New England
    I am glad to see an official/supported version of Winclone back from the dead again. This makes lots of Windows on Mac operations so much easier!

    My order will be placed as soon as I get home!

    I will also link to this thread from the MR Guide.


  3. Cennipe macrumors newbie

    Mar 19, 2012
    This is exactly what I'm looking for how to do! Right now, I'm unclear about two things though.

    One, when you say Mac2, are you simply referring to your specific computer and, thus, generically, the Mac partition?

    The second being, from all I can tell, Winclone is used just for making a backup image, and thus only would be needed if things go badly (I do know that a backup image is a must for this sort of thing). Doesn't Windows 7 Ultimate have something in it that will make a backup image for you, thus eliminating the need for Winclone?

    Thanks for posting such thorough instructions for this operation; best answer I've seen yet!
  4. heliora macrumors newbie

    Apr 4, 2012
    apart from the first step, i followed vesposit's guide in resizing my boot camp partition, and nearly had a heart attack lol.

    as a background i'm on a mid-2011 macbook air running the latest Lion 10.7.3 and installed Windows 7 64bit, initially allocated 50gb to Windows which wasn't enough, so had to resize it

    i was being cheap and didn't wanna spend money on Winclone, and couldn't be bothered with backing up a Windows system image as my external hard disk wasn't formatted in NTFS and it's encrypted by Time Machine and i wasn't sure if i could format the free space in it without screwing up anything and i couldn't be bothered waiting to decrypt and so on

    so decided to just risk it and went straight ahead with resizing the boot camp partition with Partition Wizard after step 2.
    immediately after that i couldn't boot into windows 7 with the message showing there's an error trying to read the boot configuration data, that's when i nearly had a heart attack as i thought it's gg i'd have to start over with reinstalling windows and transferring data etc

    but in the end i managed to fix it after booting using the usb file created by boot camp assistant and went into command prompt and typed in "bootrec.exe /fixmbr" and other commands

    after that i managed to boot into Windows 7, thank god

    however i notice two quirks, first is when i press option while restarting the macbook air, usually i only see 2 boot options, that is mac or windows, however now i see recovery disc too (most probably Lion recover).
    second is when i log in to Lion, in Disk Utility i could still see that there's free space in the HD not taken up, even though in Windows i could clearly see the boot camp partition has taken up all the free space

    i will fill up the boot camp partition and see what mac says in disk utility
  5. balamw Moderator


    Staff Member

    Aug 16, 2005
    New England
    Actually Winclone is used here as the primary agent to resize the partition and restore it to bootable status. The backup is somewhat incidental. The built in Win7 backup and partition tools don't always "play nice" with the Mac OS X parts of your system and you could easily end up with an unbootable system.

  6. heliora macrumors newbie

    Apr 4, 2012
    but he's using Partition Wizard to resize the Windows partition

    I think you're right and Winclone might be the better option, because currently what's happened to my boot camp partition is it's no longer accessible in mac, it just shows a shaded grey and is unmountable

    also the NTFS partition i created in my external hard disk with Partition Wizard isn't even viewable in Disk Utility, i could only see the mac and exfat partition created earlier with Disk Utility

    i'm by no means an expert but i think mac isn't reading the MBR or something correctly on the partitions created in Windows with Partition Wizard, zz it'll be good if somebody can help me on this, as i intend to use Virtualbox to open boot camp and it can't be done at the moment
  7. heliora macrumors newbie

    Apr 4, 2012
    ok i've a major ass problem now, after logging into Mac, i've lost access to Windows!!! Disk Utility still shows the incorrect boot camp partition, but when i restart there's no option to boot into Windows at all, and booting into the Windows installation USB disk also doesn't show any Windows 7 installed at all

    omg this totally sucks, i suspect it's because i used Disk Utility to verify and repair my mac internal hard disk and in the process somehow corrupted the MBR or something

    any expert's help would be highly appreciated, in the mean time i'm gonna try to fix it, wish me luck
  8. vesposit, Apr 5, 2012
    Last edited: Apr 5, 2012

    vesposit thread starter macrumors newbie

    Mar 20, 2012
    Yes MAC2 is just name for my computer in my office.

    yes... in my notes MAC2 just refers to my Macbook #2 in my office...

    Also yes you are right that Winclone is just for backup... it is not just file backup but a image of the whole partition so if things go very badly you could create a new Bootcamp partition from MAC and use Winclone from Mac to restore the windows OS and files to the new partition.

    In fact... Winclone has detailed instructions on using this method to increase the size of your bootcamp win7 partition.... they use Winclone to make a image or backup of existing Win7 bootcamp partition, then in Mac disk utility you blow away the bootcamp, lose your win7, recreate the bootcamp partition now larger... then use winclone to re-install the win7 bootcamp image just made... it puts back you win7 and file and increases the win7 partition to the new larger size... I have used this method in pas on Mac1 and works fine... but just takes longer.

    So I suggest first MAKING the Backup of your partition with Winclone... then use the quick method above. In worst case you have to just re-create the bootcamp partition from scratch and then re-install from the backup image just made with Winclone...

    And I suggest having you files backed up somewhere else on your network, external drive or cloud backup just in case it all goes belly up... and then do a complete win install w/ apps and files... yikes @#$%^

  9. cariocap macrumors member

    Nov 27, 2011
    Rio de Janeiro - Brazil
    thanks heliora for your tip to run a few commands to fix the status :0xc000225. File: \Boot\BCD corrupted.

    Just to let other guys know them, the steps are:

    1) boot with your windows 7 disk
    2) select your language
    3) select repair and follow instructions
    3) go to command prompt and execute the commands bellow:

    bcdedit /export C:\BCD_Backup
    cd boot
    attrib bcd -s -h -r
    ren c:\boot\bcd bcd.old
    bootrec /RebuildBcd
    bootrec /fixmbr
    bootrec /fixboot

  10. James747 macrumors newbie

    Apr 18, 2012
    One small detail

    Great tips ty!

    I followed your steps and when I log in on the Win 7 side it shows the modified partitions properly but when I log in on the Mac side Disk Utility still shows the Bootcamp partition as originally created at 42gig. ( Before i had increased its size with the MiniTool Partition Wizard Home Edition v7.1)
    Any ideas?

  11. jsoto, Apr 24, 2012
    Last edited: Apr 24, 2012

    jsoto macrumors regular


    Jul 27, 2010
    I have been in the midst of upgrading my stock hdd from 500 GB Hitachi 5400 RPM to WD 750 GB Caviar Black. The built in Win7 backup and restore tools work but and I say with a BIG BUT... Mac OS X doesn't see Bootcamp for setting as start up disk. Also Mac OS X reports the wrong informatio as disk size and such. I am just going to clone OS X with Carbon Copy Cloner which works like a champ and just rebuild the Bootcamp partition. Nice to see WinClone resurrected from the dead. I might try the new WinClone out and see how it works out now that I am tempted to try :)

    Edit: Win7 Backup and Restore tools work great on native Windows boxes. With Mac's it overwrites the bootcamp partition and somehow overwrites Mac OS X in seeing the Bootcamp data correctly. Bootcamp will work fine but not the way it was designed by Apple in mind. Best to use the new WinClone or build from scratch. At least you can clone OS X or use WinClone and CCC for the win!
  12. leftheaded macrumors member

    May 10, 2010
    Followed the first post instructions, but skipped cloning an image for backup purposes (I was about to reformat anyway, so took the 8 hour risk since I didn't want to drag this into tomorrow!).

    One thing to note for others:

    Turn off FileVault encryption because DiskUtility will not be able to resize your Mac partition.

    Once that was done, I resized the Mac partition, rebooted to Win7, installed v7.7 of MiniTool, extended the Win7 partition, rebooted (as instructed by MiniTool). 75GB reallocated - Done. Whole process took minutes on a Vertex3 240GB SSD. Longest part was decrypting the Mac Os ... said 18 minutes.
  13. Quantum3 macrumors newbie

    Oct 26, 2010
  14. fusion71 macrumors newbie

    Jun 14, 2013
    Just wanted to suggest a few tweaks to the partition wizard bootcamp resize method

    • leave 128mb of free space between osx and bootcamp partitions to avoid "loaderspace error" issues with osx disk utility

    • After using partition wizard to extend the windows partition, OSX disk utility will fail to mount the bootcamp partition. This happens because Minitool Partition Wizard only updates the MBR partition table after extending the windows partition, not the GUID partition table. Disk utility references the GPT and thus is "unaware" of the changes made to the MBR and can no longer mount bootcamp without it being reconciled with the MBR.

    To fix, you can use the GDisk utility in OSX (download here .Please read documentation carefully ). I would first recommend backing up all your data (eg using time machine for OSX, windows backup utility for windows) then resync GPT to MBR table with GDisk- steps summarised below:

    sudo gdisk /dev/disk0 (assuming disk0 is your drive containing both OSX and bootcamp)
    type '?' for options

    choose 'b' to first backup your GPT table to a file (therefore can restore changes if something goes wrong)
    choose 'p' to print current GPT table and note down
    choose 'x' for extra functionality (experts only)
    choose 'o' to print MBR table details (write these down, especially the start and end sectors for the bootcamp partition - usually partition number 4, type 0x07)
    type 'm' to go back to main menu
    'd' to delete bootcamp entry in the GPT (ie partition 4)
    'n' to re-add bootcamp entry into the GPT using the correct starting and ending sectors printed from the MBR table above
    'w' to write table to disk

    Afterwards choose 'v' for GDisk to confirm both MBR and GPT are in sync
    'q' to quit GDisk

  15. ssette macrumors newbie

    Apr 1, 2014
    Tanks a lot !
    This works and solves a lot of problems. :)
    (btw i can now use the bootcamp partition as vmware VM)


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