The Active Directory Schema Snap-In is not an option in MMC by default. If it’s missing from the Add/Remove Snap-In screen, perform these steps.
- Select the “Start” button, then type “CMD“.
- Right-click “Command Prompt” and select “Run as Administrator“.
- Type the following, then press “Enter“:
- You should receive a message that registration succeeded.
Now you should be able to add the snap-in using these steps:
- Hold the Windows Key and press “R” to bring up the Run box.
- Type “mmc“, then press “Enter“. The Microsoft Management Console opens.
- Select “File” > “Add/Remove Snap-In“.
- Select “Active Directory Schema“, then select “Add“.
- Select “OK“.
The Active Directory Schema option will now be available to use.