The termsecurity IDis sometimes used in place of SID or security identifier.
Why Does Windows Use SIDs?
Decoding SID Numbers in Windows
All SIDs start withS-1-5-21but will otherwise be unique.
A few SIDs can be decoded without the instructions linked above.
For example, the SID for theAdministratoraccount in Windows always ends in500.
The SID for theGuestaccount always ends in501.
You’ll also find SIDs on every installation of Windows which correspond to certain built-in accounts.
So, in that respect, the above summary is probably all you should probably know about SIDs.
However, if you’re more than casually interested in security identifiers, Microsoft has afull explanation of SIDs.
The .SID letter group is also used in somefile extensions.
FAQ
You canfind a user’s SID using the Windows Management Instrumentation Command.
In Command Prompt, typewmic useraccount where name=“USER” get sidreplacing USER with theusername>Enter.
Go toC:\Windows\System32\Sysprepand runsysprep.exe.
grab the Generalize checkbox, then selectOK.
When Sysprep is done, restart the computer.
