
You would think that you can have full control of your Windows when you are its 
Administrator. However, when you try to delete some of the files from your computer, a Folder Access Denied message will pop up and say “
You require permission from TrustedInstaller to make changes to this folder.” Looks like you still don’t have the final say on your operating system.
In order to protect core files in Windows, Microsoft has created an 
NT SERVICE\TrustedInstaller account in Windows to own these important files and prevent them from being removed. Therefore if you try to change or delete any of these files, a 
“You require permission from TrustedInstaller” will appear and stop you from proceeding.
But If you know what you are doing and persist in your action, here is how to claim the privilege from TrustedInstaller:
1) Right-click on the file or the folder you want to change or delete and select 
Properties.

2) On the Properties window, open the 
Security tab and then click on 
Advanced.

3) We are now going to change the Owner On Advanced Security Settings window. On 
Windows 10, you can click on 
Change next to
 Owner: TrustedInstaller.

But on 
Windows 7 or earlier versions, you need to select the 
Owner tab and hit 
Edit. And on the window popping up, click on 
Other users or groups.

4) On the window popping up, type the 
user name you are using on this computer into the box and click the 
Check Names button. Windows will automatically check and complete the full object name. Then click on 
OK.

5) Tick the box next to 
Replace owner on subcontainers and objects if you want to apply the ownership changes to all the subfolders and files. Then hit 
OK to close this window and go back to Properties.

On 
Windows 7, the 
Replace owner on subcontainers and objects box is below the 
Other users or groups button.

6) Click 
Advanced again. Then click on the 
Change permissions button under Permission entries
 

7) Click on 
Add. On the Permission Entry window, click on 
Select a principal. A window similar to the one that appeared in 
step 4 will show up again and you need to 
repeat step 4.

Tick the box next to 
Full control in the 
Basic permissions section, and hit 
OK.

Check 
Replace all child object permission entries with inheritable permission entries from this object. After that, click on 
OK all the way out.

For 
Windows 7, you need to click on the 
Change Permission button on the 
Permissions tab to see the 
Add button. Click on that and 
repeat step 4. After that, check the 
Allow box of 
Full control and click 
OK.

Check Replace all child object permissions with inheritable permissions from this object. Then click on 
OK all the way out.

8) Now you can delete the file that you have just changed ownership without the “You require permission from TrustedInstaller”
 message bothering you.
You can also apply these changes to other protected files to take full control of them. But remember you should always understand the likely consequences of your full control and know what you are doing before you take any further action.