Adjusting the MBR (SRP) partition in Windows 7 to prepare for Windows 10 Upgrade

MBR System Recovery Partition

Adjusting the MBR (SRP) partition in Windows 7 to prepare for Windows 10 Upgrade

Adjusting the MBR (SRP) partition in Windows 7 to prepare for Windows 10 Upgrade 639 479 Jason Stadtlander

As many of you may be aware, I am in IT by trade and recently many people have been trying to perform the free upgrade to Windows 10 that is being offered by Microsoft until July 1, 2016.

One problem many people run into is not having enough space on the System Recovery Partition (SRP) which is a special little 100MB space on your hard drive that Windows uses for storing special boot files in case your operating system has problems.

The following will show you how to free up space on your SRP so that you can perform the operating system upgrade to Windows 10. Keep in mind, this is a sensitive partition, so be sure to follow exactly as I have outlined below and you should be fine. I have tested this and it works perfectly. Usually it will free up an additional 40-50MB of space.



This makes a permanent, but small, increase in the available space of the SRP (system recovery partition).

Prepare the Recovery Partition and Backup Permissions

  1. Press the Windows key + R. In the Run window that comes up, type msc and press Enter.
  2. Select the partition marked System Reserve. Press-and-hold or right-click on it.
  3. Select Change Drive Letter and Paths.
  4. Choose Add.
  5. Enter Y for the drive letter.
  6. Tap or click OK.
  7. From the Start menu, search for cmd. Right-click Command Prompt from the search results, and select Run as administrator.
  8. In the command prompt, type Y: and hit enter to switch to that drive.
  9. Type the following and press enter: takeown /d y /r /f .
    You must include the space and the period after the “f”, or the command will not work properly.
  10. Type icacls Y:\ /save %systemdrive%\SysResrvBU.txt /t to back up the current permissions.
  11. Type whoami and press Enter, and then record the user name.
  12. Type the following command:
    icacls . /grant <username you got from whoami>:F /t and press Enter.
    Note: Do not put a space between the username and “:F”, or the command won’t work.

Truncate the NTFS Log

  1. Check the size of the NTFS Log first. From the Command Prompt, type the following and press Enter: chkdsk /L Y:
    1. If the size is less than 5000KB, you do not need to truncate the file.
  2. To truncate the file, type the following and press Enter: chkdsk /L:5000 /X /F

Restore permissions

  1. Press the Windows Key (windows key) + R
  2. Enter the %systemdrive%\SysResrvBU.txt file and press Enter.
  3. A notepad or other text editor application should open with the contents of the file. On the first line you will notice that it’s blank. Enter a single “.” (without the quotes) and save the file.
    NOTE: Because it’s on the system drive, you might have to save it elsewhere and then copy and paste it to the system drive location manually.
  4. Close the text editor and go back to the command prompt that you have open.
  5. Type the following command: icacls Y:\ /restore %systemdrive%\SysResrvBU.txt /c /t and press Enter.
    1. A message may display indicating some files failed while processing – this is normal as these files have been deleted subsequent to backing them up.
    2. If the amount of successful files is none, then the command was executed incorrectly; you must have some files successfully processed before continuing.
  6. Adjust the ACL back to System by typing the following:
    icacls . /grant system:f /t and press Enter.
  7. Set the owner of the drive back to System by typing the following command:
    icacls Y: /setowner SYSTEM /t /c and press Enter.
  8. Go back to Disk Management and Refresh the data to confirm if the SRP now has a greater percentage of free space. If so, the drive letter can be removed at this point.
  9. Right-click the System Reserved Partition.
  10. Select Change Drive Letter and Paths.
  11. Choose the Y:
  12. Select Remove.
  13. Click OK.


1 Comment
  • 28 Jul 2016

    Dear Mr. Jason P. Stadtlander,

    Thank you so much for this post. I wish I had found it first! What I did find and use was this one from Microsoft:
    . Now I have a problem, and hope that you can help. This is for a 64-bit Windows 7 Home Premium system, trying to upgrade to Windows 10. This is the last machine needing to get the free upgrade, and time is running out.

    The instructions were followed exactly under “Windows 7 with MBR partition” through #1. j. No language folders were deleted for step #1. k. Under #2., the NTFS Log size was 2048 KB, so the file was not truncated. Step #3. was followed, with the USN journal being deleted and then recreated. That changed the 100 MB partition from 2 MB free to 61 MB free. So far, so good.

    Step 4. a. is where the problem lies. The message received when executing the listed command is:
    “No such file or directory
    Successfully processed 0 files; Failed processing 0 files.”

    Searching for solutions and trying various configurations of that command for three days didn’t change that message.

    It was at this point that I found your post, and realized that the instructions had NOT included backing up the permissions. I haven’t been able to locate the correct file name where the permissions reside, but NTFSp.txt doesn’t seem to be it. Search was done with showing hidden files, folders, drives and protected operating system files. Search was also done for SysResrvBU.txt, without success. I do have an old (of several months) image backup on an external drive that I can access, if necessary.

    With the warning of “you must have some files successfully processed before continuing,” I’ve been leery of continuing on with step #4. b.-4. i. until this permissions issue is solved. To prevent further problems, the computer has not been turned off or rebooted. It’s also been kept off the Internet since starting this procedure, as all security software was disabled in preparation for the upgrade.

    Several Web sites have offered solutions for resetting all permissions, but they all seem to have problems in one scenario or another. I normally only try solutions from official sources, such as .

    So, your advice please. Should I try to locate the old permissions folder on the image backup, copy it (or possibly use the icacls Save switch on it?), and somehow restore it to the correct location? OR Should I try to continue on with the procedure from step #4. b.-4. i. and then try to do a system restore, which may not totally fix the permissions issue? OR Should I try to reset them manually on the Y:\ drive? OR Try something else? ( looks simple.)

    Since the purpose of all this was to upgrade to Windows 10, is it likely that if I just complete the #4. b.-4. i. procedure as the system now sits, that the upgrade would be successful? If it was successful, I’m assuming that the new O/S would reset the permissions anyway, making the rest of this problem go away. Is that correct? Other Web sites with similar instructions to extended the partition didn’t bother to save or restore permissions, which seems a little odd to me. They didn’t even remove the Y:\ drive until after their Windows 10 upgrade was successful (see , for example — noting that the “Mark partition as Active” solution there is a VERY bad idea).

    I’m looking forward to hearing from you.



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