Folder permissions and access Windows 10

murphydavid

First this is my own personal PC and I.ve had it from new and initiated it. I am (should be) both user; administrator; and general dogs body. However I had an access issue (no permission) to enter a folder. I can understand Microsoft want to protect me from myself but - give me warnings etc but not make it as hard as a chinese finger trap. Anyway I did gain access but I was curious to know if I could get a bit more in-depth knowledge. The first step to gain access is by changing the owner to a more friendly one. I do this via rightclick on said folder - properties - security - advanced - change owner Which brings me to "select user or group". At this point there is no drop down box just a type here nor any immediately apparent list of users or groups. On my PC at this point for this folder the name I am trying to change is "Trusted Installer". I make a careful note in case I want to revert. Anyway I change the name to one I know. At this point curiosity kicks in and I try to change it back and type Trusted Installer into the box only to be told that that name can't be found. So what names are there and why has that one disappeared. Google search was no help so I proceeded to hit Advanced and Find Now and was surprised to find a multitude of names but Trusted Installer was not one of them. Anyway out of curiosity I selected one (Administrator) hit OK and it put a different name (DAVID) coincidentally my first name in the box. Further more the names of the "principals" I can give full access to do not coincide with the names of the owners of the folders.
So to summarise.
When trying to give full access permission to a folder the names of the principles have no real meaning to me.
The names of the owners don't match the names of the principles.
There are a multitude of possible owner names to select from but when you select one; the name listed as the owner changes but is not the same as the name you select. 
You can finally get access permission for windows explorer but for me its all just a selection of random names.
Owners disappear for no reason.
And possibly (not sure) by getting permission for windows explorer I may have blocked permission for another vital program that was using that folder and I can't revert back.
And possibly I may have granted access to a hacker on the net and I can't revert back
Apart from telling me not to mess with things I don't understand. Any helpful insights or definitions of the various options and results would interest me. Thanks

arciere

If the folder has restricted access it is likely because it is a system folder that should not be touched, unless you know what you are doing (and it doesn't look like you do, no offence).
The best thing you can do now is to do a system restore.

Neil_Jones

The problem tends to stem from the fact there are actually four levels of permissions on Windows machines - guest, limited, administrator and system.  Administrator is not the same as system.

Anyway the long list of names you see in the "search" box is normal.  To be honest you shouldn't really been playing with those anyway.  There are only a handful of circumstances where you would even need to do this, and curiosity isn't one of them.

Depending on what you've changed and where it was (and whether System Restore was enabled or not - by default on a clean install it isn't) determines where you go from here.

murphydavid

My start point was not curiosity but a legitimate task using a microsoft app that came up with access denied. That was: I wrote a script for microsoft power shell to be activated by built in task scheduler.  The purpose was to automatically; at set times; copy a file containing data created by me in a folder on my C drive created by me onto an external hard drive installed by me. I had full access to do this manually using windows explorer but the power shell app gave me access denied. I used the same script slightly modified to copy a file from one hard drive to another without any problem. So it turns out power shell could not access my own folder on my C drive. The solution was to change the owner of the C drive which was set at Trusted Installer to my name and then give myself full control of my C drive. In my opinion quite bizarre and if I ever need to change it back Trusted Installer can't be found so I would need to try restore but fortunately I don't want to because my original problem is solved and my PC is still running fine. Still wondering why I can't find a web page that describes the intricacies of it all. I would add that I maintain a full disc image backup of my C partition just in case. And also have a task scheduled to create a restore point daily.

Neil_Jones

Access denied in Powerscript normally means you need to run the script as administrator which should on its own provide the elevation needed for the copying of file, especially if they were in "protected" folders like Documents to begin with.

You shouldn't have needed to change any permissions.

murphydavid

Neil_Jones said:

Access denied in Powerscript normally means you need to run the script as administrator which should on its own provide the elevation needed for the copying of file, especially if they were in "protected" folders like Documents to begin with.

You shouldn't have needed to change any permissions.

Thanks. I will try that next time.