Windows 10: Worried about this Unknown User S-1-5-21-...-1004

I do not recall ever creating a group sharing any of my files. S-1-5-21-*********-**********-**********-1004 is an unknown user who is literally everywhere all up in my permissions on all my personal and valuable software libraries. I've read that this could have come from me deleting a user profile... the thing is I did but over a year ago... and this thing just made its appearance within the last week or so around the same time I noticed that sharing has been turned on on like all my main file indexes. My mother in law works for a Bank of let's say "Not America"... and the recent Covid-19 and subsequent quarantine has made it so she works from home now, our home, and shes doing this work for them via the houses shared ISP. Now I haven't asked her if they made her install some extra software on her work laptop that potentially reveals every packet of info up and down being sent by not only her but everyone else in the house and not just that but this software could potentially have read my IP and MAC address and have to treat me like a potential threat and sent some kind of corporate trojan in to give them access my PC? via enabling sharing and granting this unknown user all the permissions... sorry about the tinfoil burning conspiracy that could turn out to not at all be whats happening, but that's my situation so far. Am I being hacked ? what can i do? again the profile is "Unknown User S-1-5-21-2504284481-4194355809-**********-1004" none of the other forums i looked at has the specific "S-1-5-21" sequence... I just want to know what someone more knowledgeable could recommend I take as the next course of action.

:)

 

S-1-5-21-119163587-1573839180-90999006-1001

I give up, what is it - and what's a "security ownership panel?"

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FYI...

Well-known security identifiers in Windows operating systems:

https://support.microsoft.com/en-us...rity-identifiers-in-windows-operating-systems

Unknown User in security settings s-1-5-21 ... 1001

Unknown User in security settings s-1-5-21 ... 1001 - Can someone please review? - Virus, Trojan, Spyware, and Malware Removal Help

Account Unknown (S-1-5-21-130066488-785734366-1129733132-1000)??

Account Unknown (S-1-5-21-130066488-785734366-1129733132-1000)?? - Windows 10 Help Forums

How to understand the anatomy of security identifiers

How to understand the anatomy of security identifiers

 

Account Unknown (S-1-5-21-130066488-785734366-1129733132-1000)??

Hi, recently whenever i have checked the security tab of my files, I see the above thing: Account Unknown (S-1-5-21-130066488-785734366-1129733132-1000), should i worry about this?? a hacker or something?? how can i delete this, it has "special permission". Also there is another account similar to this under INTERACTIVE, whats going on?? Hope someone can help. Thank you.
Keith

 

HKU S-1-5-18 TO S-1-5-21-1377943898-483413162-3496510108-1001 AND S-1-5-21-1377943898-483413162-3496510108-1001 Virus

Hiii,

I have some how downloaded this virus HKU S-1-5-18

HKU S-1-5-19,

HKU S-1-5-20

S-1-5-21-1377943898-483413162-3496510108-1001 S-1-5-21-1377943898-483413162-3496510108-1001 _classes

I have got installed with so many viruses ,and get affected by them,

so inorder to remove them I reset my pc by removing apps and keeping only files and folders.

by doing this my windows got installed again on resetting the pc.

but this HKU s-1-5-18 to s-1-5-21 shown above virus was still in the Regedit (register keys)

I am trying to delete this folder in regedit but it is saying that unable to delete the specified values and also showing I don't have administrator permissions

After installing this viruses my Windows Defender Check Apps and Files in App & browse Control is off and greyed out

showing in defender this is managed by your administrator ,but I am the administrator



again in properties security setting this s-1-521 user account is automatically created and gained administrator permissions

so please,help me with this how to fix them and to check are there any other viruses

I tried malware bytes and emsisoft but they are unable to clean them

so please help me ,to how to get rid of this and permenantely delete them