General Computing
windows permissions ntfs read-only
Updated Mon, 12 Sep 2022 10:57:50 GMT

Making a Windows Folder Truly Read Only

I have an external hard drive. One of the root folders has the subfolders and files I want to protect. There are up to two levels of sub folders within this root folder. I want to set the permissions on this root folder, sub folders and files throughout to be truly read only meaning.

  • No creating, deleting or renaming a folder, subfolder or file - basically making it like a burned CD/DVD.

It's been three hours and I'm in circles. I've gone into the advanced permissions and set the permission for my user account to Read & execute, List folder contents and Read.

There's is something truly bizarre going on in that I look into the security tab and my account has Special permissions only checked. But when I go into the Advanced button I see my user account listed twice, once with the restricted permission, and again with Full control.

enter image description here


As already mentioned in the comment section:
The reason why you still have Full Control is because of the "CREATOR OWNER" ACE. You are the current owner of the parent and this folder.
Best would be to remove "CREATOR OWNER" in the ACL of this folder and all parent folders and additionally change the owner of all to "SYSTEM" (just click "Change" next to "Owner" in the second line of your screenshot and enter "System")

But, and that's important, you can't make an external hard drive 100% read-only just with permissions or file/folder/drive attributes.
For that you need kind of a ROM drive (read-only memory), either by design (like CD-ROM / DVD-ROM) or by a write-lock, implemented directly into the controller of the hard drive.

But both would make the entire drive read-only / write-protected.

Comments (2)

  • +0 – +1 from me. :) here you go. — Jun 05, 2022 at 11:55  
  • +0 – In the current state, this is a comment, not an answer (e.g. How is CREATOR OWNER removed? How is the owner changed to System? What directory are the ACLs set on for inheritance? etc.) — Jun 05, 2022 at 12:17  

External Links

External links referenced by this document: