Houdini License Server Annual Reactivation Guide (macOS, 2025)

Keep this guide for your yearly SideFX Houdini renewal on macOS. If the server won’t run, follow the steps exactly.

1. Clean Up Old License Server (If Stuck)

If Houdini License Server won’t start or shows “Input/output error”:

sudo rm /Library/LaunchDaemons/com.sidefx.sesinetd.plist

2. Reinstall/Repair the License Server Using Houdini Launcher (optional)

• Open Houdini Launcher (in Applications).

• Go to Modify License Server.

• Let it use the default directory (/Library/preferences/sesi) unless you have a reason to change.

• Click Modify and let it fully reinstall or repair.

• Reboot your Mac (important for LaunchDaemon to reload).

3. Confirm License Server Status

• Open Houdini License Administrator (hkey).

• Go to the Server Information tab.

• All indicators should be green:

- Running: OK

- Valid Licenses: OK

- Valid Server Code: OK

- Read Access/Write Access: OK

• If not, repeat step 2 or check for other errors (see Troubleshooting).

4. Log In and Redeem Licenses (Manual Login Recommended)

• Click Log In at the top right (do NOT rely on auto-login).

• Enter your SideFX account credentials.

• Go to File → Install Licenses.

• Select your paid or educational licenses to redeem.

• For rental/education: select “Paid Licenses” and Redeem Rental Licenses as prompted.

5. Launch Houdini & Select License

• Start Houdini from Launcher.

• If prompted, select Use Paid/Full License (not Non-Commercial/Apprentice).

• Houdini should now open fully licensed.