Solved "Account Unknown"

[Gwaihir]

Firstly apologies as I know this has been raised before. I did a search but the threads I found didn't give any answers that made sense to me.

When I look at the permissions for a text document I find among the list of accounts the following:-

"Account Unknown(S-1 -5-21 -5372119434272335595-134997445-1000)"

When I open the User Accounts in Control panel there is no such account shown, nor is it shown if I look in Local Users and Groups in Computer Management.

Could someone explain, preferably in simple terms, what this entry is, whether it is desirable to get rid of it and if so how?

Thanks for any help.

 

[Maguscreed]

It appears to be a temporary permission, the SID or security identifier number checks out so I do not believe it to be malicious though if that was your concern.

 

[Dave Atkin]

Hello,

Its probably a user account that has been removed or recently deleted.


The long number is a SID (Security Identifier) number. You can remove it via the security tab in the properties (Right click on the file and select properties, click security).

See:
(en.wikipedia.org/wiki/Security_Identifier).


Dave

 

[Gwaihir]

Thanks for your responses. Yes, my primary concern was that it might have been created by malware in order to gain access to my system. A secondary worry was that if it was legitimately created by the system then deleting it might make the file inaccessible.

Dave, I haven't created or deleted any user accounts since installing the OS. I did do a re-install of the OS since the original installation, but this was after changing partition sizes and reformatting the partitions so was a clean install.

I think I'll try removing it and see what happens.

 

[Dave Atkin]

Is it a file you have copied from another PC? Sometimes they retain the permissions.

Do a Malware scan just to be sure but I wouldnt worry about it too much.


Dave.

 

[Gwaihir]

Hi Dave,

That's an interesting question. When I upgraded from XP I copied all my user files to an external drive then copied them back onto the new system. Maybe that could be the explanation? If so then presumably this would apply to every file.

Interestingly when I removed the Account Unknown from the list of permissions ALL the permissions were removed and I then had to individually add back the ones I wanted.

 

[Dave Atkin]

Hi Gwaihir,

Yes it could explain the permissions from an old user. It shouldn't have removed the other permissions as well but as long as you can gaion access to it then again dont worry too much unless its causing you a problem.

Do a virus scan anyway - Just to be safe .


Dave

 

[Gwaihir]

Hi Dave,

No, no access problems after deleting it. I've checked a few other files and they all have it so it looks like you've nailed it.

Far too many files to change so I'll just leave alone as long as it's not malicious. I have Avast free anti-virus and will try a scan.

I'll think I'll mark this thread as solved now. Many thanks for your help.

 

[Dave Atkin]

Anytime .

Dave

 

[ankrotachi]

There were multiple account unknown on mine, and one cannot be removed, was not originally an admin, but has full control, what do I do?
The attached picture shows you cannot remove the selected account from the permissions:

 

[ankrotachi]

Don't worry, I found out that a lot of the folders that had this bug were also shared with an "Unknown contact" to remove both of these: right click on folder>properties>sharing tab>share button> drop down menu next to Unknown Contact>remove>share

This will remove the permissions and unknown contact sharing

 

[mohavepc]

ankritachi:
I would suggest starting your own thread as a start.

 

[dragonfish]

Account Unknown s-5-2-1.....

responding to an old post. ( but this is my first.practice i guess )

RE. Account Unknown s-5-2-1.....
I recently needed to download win 7 pro and since it said it was not valid (which it was on a refurbished machine) I had to get help from Microsoft Remote assistance and they verified it was genuine and downloaded it for me.
Now. Question . Could the "Account Unknown s-5-2-1....." be there user profile that they used to access my computor to download the ISo ?

 

[Megahertz07]

Welcome to the forum.
When you buy a refurbished computer, you don't know what is in it. It can have malicious programs installed, back doors open etc.
If I were you, I would do a Factory Recover or a Clean install using your COA license.
If you wish to do a Factory Recover or a Clean install and need assistance, please let us know.