Follow these easy steps to display a table of user names and their corresponding SIDs:
Time Required: It'll take less than a minute to find a user's SID in Windows via WMIC:
Open Command Prompt.
Once Command Prompt is open, type the following command exactly as shown here, including spaces or lack thereof:
wmic useraccount get name,sid
and then press Enter.
You should see a table, similar to the following, displayed in the Command Prompt window:
This is a list of each user account in Windows, listed by user name, followed by the account's corresponding SID.
Now that you're confident that a particular user name corresponds to a particular SID, you can make whatever changes you need to in the registry or do whatever else you needed this information for.