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Fix Permissions Changes Preventing Windows From Booting (Windows 7 / Vista)


Administrator, BSOD Kernel Dump Expert, C++ OOP
May 23, 2012
Fix Permissions Changes Preventing Windows Vista or Windows 7 From Booting

Permissions problems often result in Windows loading to a black screen with a cursor and then not loading any further.


Permissions changes can result in Windows not being able to boot. The changes may result from user error or from a virus/malicious item. If you know you changed permissions prior to the problems starting, proceed to step 2. Otherwise, start with step 1. to remove malicious items prior to fixing the permissions.

Scan for Viruses Offline:

Run Windows Defender Offline to check for viruses/malicious items. You may also want to read through Free bootable antivirus rescue CDs for other malicious item removal tools that run outside Windows. If you want further help from our security experts, start a thread in the Security Arena.​

Access a Command Prompt Outside Windows:

Access a Command Prompt using the Windows Install Disc:

  1. Insert the Windows Installation Media and restart your system.
    • Before you can use the installation media, configure your BIOS for the proper boot order. The installation media should be the first option in the boot menu, i.e. your CD/DVD drive or USB drive.

    • Refer to your system manual for steps to enter the BIOS and change boot order settings. Most system manuals can be found online through the system manufacturer (Dell, HP, etc.) or motherboard manufacturer (Gigabyte, ASUS, etc.).

    • If you cannot find your installation media, please contact your system manufacturer (Dell, HP, etc.) to replace missing recovery discs or contact Microsoft to replace a missing retail copy. If you were not provided with installation media, you may need to purchase a retail copy from an online or local store.
  2. Press a key when given the message to Press any key to boot from CD or DVD...

  3. You'll see a screen that says Windows is loading files...; this may take a few minutes depending on the speed of your DVD drive or USB drive.

  4. Choose your installation options and click Next.


  5. Choose Install Now.


  6. Press Shift + F10 when the installer loads.

Access a Command Prompt from the Windows System Recovery Options:

Access the Windows Recovery Options and then select Command Prompt.

Reset Permissions:

  1. Once you have a command prompt available, check the directory structure of each drive as follows. In the example below, drives c:, d:, and e: are checked, but you may need to check other drives on your system. The drive will not be X: since that is the virtual drive stored in memory for the Windows installation files.

    dir c:
    dir d:
    dir e:
    The example below shows the Windows directory on drive c:


  2. Change to the drive containing your Windows directory; the drive is C: on the example system:

  3. Set up your permissions for your Windows directory:

    icacls Windows /t /c /grant "NT SERVICE\TrustedInstaller":(F)
    icacls Windows /t /c /grant SYSTEM:(M)
    icacls Windows /t /c /grant SYSTEM:(F)
    icacls Windows /t /c /grant Administrators:(M)
    icacls Windows /t /c /grant Administrators:(F)
    icacls Windows /t /c /grant Users:(RX)
    icacls Windows /t /c /grant Users:(GR,GE)
    icacls Windows /t /c /grant "CREATOR OWNER":(F)
  4. Set up your permissions for your Program Files directory:

    icacls "Program Files" /t /c /grant "NT SERVICE\TrustedInstaller":(F)
    icacls "Program Files" /t /c /grant SYSTEM:(M)
    icacls "Program Files" /t /c /grant SYSTEM:(F)
    icacls "Program Files" /t /c /grant Administrators:(M)
    icacls "Program Files" /t /c /grant Administrators:(F)
    icacls "Program Files" /t /c /grant Users:(RX)
    icacls "Program Files" /t /c /grant Users:(GR,GE)
    icacls "Program Files" /t /c /grant "CREATOR OWNER":(F)
  5. Set up your permissions for your Program Files (x86) directory if you have 64bit Windows:

    icacls "Program Files (x86)" /t /c /grant "NT SERVICE\TrustedInstaller":(F)
    icacls "Program Files (x86)" /t /c /grant SYSTEM:(M)
    icacls "Program Files (x86)" /t /c /grant SYSTEM:(F)
    icacls "Program Files (x86)" /t /c /grant Administrators:(M)
    icacls "Program Files (x86)" /t /c /grant Administrators:(F)
    icacls "Program Files (x86)" /t /c /grant Users:(RX)
    icacls "Program Files (x86)" /t /c /grant Users:(GR,GE)
    icacls "Program Files (x86)" /t /c /grant "CREATOR OWNER":(F)
  6. Set up your permissions for your Users directory:

    icacls Users /t /c /grant SYSTEM:(F)
    icacls Users /t /c /grant Administrators:(F)
    icacls Users /t /c /grant Users:(RX)
    icacls Users /t /c /grant Users:(GR,GE)
    icacls Users /t /c /grant Everyone:(RX)
    icacls Users /t /c /grant Everyone:(GR,GE)
  • The icacls commands may take some time to complete depending on the size of your directories and the programs installed. Please be patient.

Last edited:


New member
Aug 14, 2015

I realize this was written back in 2012 but hopefully you will see this message. I've been having issues with windows booting to a black screen with pointer and thankfully I found your guide. "Icacls commands may take some time" is the understatement of the day when there are 30 of them to run. My DOS is very rusty but I'm wondering if you can run multiple lines of this at once recovery command prompt? Would it just be "COMMANDA & COMMANDB & COMMANDC"? i.e.

icacls Windows /t /c /grant SYSTEM:(M) & icacls Windows /t /c /grant SYSTEM:(F)

Is this inadvisable?

Any help you can provide is hugely appreciated. Thanks again for the guide.



New member
Jul 10, 2018
Just wanted to say a massive thank you to the OP.....!!! I'm also bumping a very old topic but the steps laid out worked flawlessly on a Windows 7 x64 machine. I'm so glad I found this thread as was literally about to give up and wipe it after spending many hours with it.

What prompted me to get here was a Microsoft forum where someone also posted some useful commands using 'cacls'. But I think because it used the group 'Everyone' and that group may not have existed on my machine it didn't work properly (when I rebooted the login screen would be flashing and no where to enter password etc.)

In regards to the guy above me, I'm only about 3 years late with my help but there is a trick to paste all the commands in via notepad to make it more manageable. Copy the command lines from this thread in a .txt file and save to a USB stick, insert said USB stick into the problem machine. On your CMD window type 'notepad'. Now open the .txt file you saved.

Copy each block of commands and paste them in - Now with a bit of luck it should automatically do all the work (you might need to hit Enter on the last one in each block).

Stupidly I created this problem myself by plugging the OS drive into a different machine (Windows 10) externally to browse the files... I guess Windows 7 didn't like me doing that, but I had the last laugh!!!

Knowledge is power, share it well !

Thanks again :)