Solved "unknown Users" are listed in Properties/Security of a folder.

[BigZ]

"unknown Users" are listed in Properties/Security of a folder.

PROBLEM: "unknown Users" are listed in Properties/Security of a folder.

I have Windows 7, 64-bit.

The Properties/Security box of my "C:\Users\[my name]" folder lists two Users called
"Account Unknown (S-1-5-21-879640176-2077098734-2292519611-1001)"
and, "Home Users", in addition to the legitimate Users "SYSTEM", "Administrators", and "[my name]".

After deleting the computer's Limited Acct, the 2 Users are still listed.

"S-1-5-21-879640176-2077098734-2292519611-1001" is not found by the Yahoo Search Engine. The Windows folder-specific search engine for "C:" and for "Users" searches essentially indefinitely. That for the folder named after myself finds nothing.

Especially regarding "S-...", is this caused by malware ? Would deleting either or both of these Users cause harm ?

Thanks.

 

[logicearth]

Account Unknown can come from a previous installation or from an account that previously existed but has since been deleted. And you will not find anything within the search engines about the long string of numbers because it is unique on most computers. See: https://en.wikipedia.org/wiki/Security_Identifier

 

[BigZ]

Thanks, logicearth, for the solution and for the reference to Wikipedia. I removed the 2 users from the folder's Properties/Security list.

To all forum users, please consider this thread solved and closed.