This wikiHow teaches you how to find another user's SID (Security Identifier) on a Windows computer.
Step
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Step 1. Press Win+X key
This will open the Windows “power user” menu in the lower left corner.
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Step 2. Click Command Prompt (Admin)
A confirmation message will be displayed.
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Step 3. Select Yes
The command prompt will be displayed in the terminal window.
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Step 4. Type WMIC useraccount get name, sid
This is a command to display the SID of all users on the system.
If you already know the username you want, use this line to replace the command above: wmic useraccount where name="USER" get sid (replace USER with the intended username)
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Step 5. Press Enter key
The SID is a series of numbers displayed to the right of each username.