Replace Windows System files without Access Denied errors

Martin Brinkmann
Jun 21, 2013
Software, Windows software

Core system files are protected by the Windows operating system so that they cannot be manipulated by users of the system or applications the user runs on the system that easily. That's a good thing as it will not only prevent users from deleting files that are needed to operate the system, but also prevent - some - malware from doing the same.

Sometimes though you may need to modify a file manually that is protected by Windows. This can be quite the frustrating experience when you notice that you do not have control over some files on your system at all.

You cannot just copy a different file version to the location the protected version is stored by Windows, as you will get access denied errors when you try to do so.

There are a couple of ways around that, for instance to take ownership of files or to boot into another operating system to manipulate the files externally.

Access denied example when trying to replace the uxtheme.dll file in the system32 folder:

Destination Folder Access Denied

You'll need to provide administrator permission to move to this folder.

destination folder access denied

You need permission to perform this action.

destination folder access denied 2


The free program can be used to replace files in Windows that are protected by the operating system. It performs the operations that you would run manually to replace those files.

replace windows system files

In particular, it does the following:

  1. Take ownership of the target file that you want to replace.
  2. Acquire permissions on the file.
  3. Backup the original file before the new file is moved.
  4. Replace the file.

To use it, simply select the original file and the replacement file in the program interface and hit the start button afterwards. The program handles everything on its own from that moment on.

Note: You need to run the program with elevated privileges. It will refuse to be started otherwise and displays a notification to you to inform you about that.

The program is really easy to use, and since it is creating a backup of the original file before it replaces it, it is relatively safe to use. You can open the backups folder of the application with a click on open backup folder in the program interface. It was located in c:\SysMate_Backup on my test system.

SysMate System File Walker is a handy program for the Windows operating system that helps you replace system protected files while the operating system is running. Note that it requires the Microsoft .Net Framework 2.0 or 4.0 (two versions are supplied.

It is compatible with all recent 32-bit and 64-bit versions of the Windows operating system.


Tutorials & Tips

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  1. BJMRamage said on October 20, 2013 at 9:24 am

    ” Long Path Tool ” is also useful in situations where you see these error messages: Cannot read from source file or disk, there has been a sharing violation, cannot delete file or folder, the file name you specified is not valid or too long, the source or destination file may be in use and many other file managing errors.

  2. Richard Steven Hack said on June 22, 2013 at 8:03 pm

    Idiots can’t make a zip file properly. I extract it using Peazip or File Roller on Linux and in both cases it produces a directory but does not extract the files at all.

    I mean, how hard is it to make a zip archive?

  3. Gonzo said on June 21, 2013 at 1:34 pm

    Other options include manually via ACL or the “Take Ownership” registry hack

  4. Midnight said on June 21, 2013 at 10:33 am

    Great tip! Thanks for sharing!

  5. ank91 said on June 21, 2013 at 6:29 am

    does it restore owner and file permission on newly copied files.

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