The SID (Security Identifier) or Windows user SID is used to identify a security principal or security group and is like a passport that is assigned to every computer during the installation of the operating system. With the SID you can assign special privileges to some user accounts or restrict privileges to some accounts. SID is a unique value that is used to identify any security entity that the OS can authenticate. A security entity can be a security principal like a user account, or a computer account, and can also be a security group. Microsoft Windows security depends on SIDs for authentication, the Windows Server makes use of SIDs to identify accounts.
You will find out that the user account name can change but the SID remains the same which still helps to identify the account. If you want to read more on Windows security you can read these: How to Find a User’s Security Identifier (SID) in Windows, New Windows 11 encryption features and security enhancements will help protect hybrid work, How to use the Windows Sandbox as a security feature in Windows 10 and 11, How to enable Secure Boot on PC to install Windows 11.
Finding Security Identifier using Command Prompt
1: Run Command Prompt as an administrator
2. Once the Command Prompt opens you can type wmic useraccount get name, sid and hit enter key, after some minutes the result will be displayed.
Finding Security Identifier using PowerShell
3. Open Windows PowerShell as an Admin and type the command below.
Get-WmiObject win32_useraccount | Select domain,name,sid
Finding Security Identifier using Registry
4. Registry Editor can also be used to find the SID on your system. Open the Run and type Regedit to launch the registry or you can just type the registry editor on the search box to launch it.
Follow the path below to get to the SIDs. You will see all users and the corresponding SIDs. HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\ProfileList
I hope you found this blog post on What Is SID (Security Identifier) and How to Find It on Windows interesting and helpful. In case you have any questions do not hesitate to ask in the comment section.