Disabling DEP will resolve your issue.
1. Start
2. Right-click Computer and choose Properites
3. Click Advanced System Settings
4. Click Settings... under Performance
5. Click Data Execution Prevention tab
6. Click Add...
7. Navigate to C:\Program Files (x86)\Lucas Arts\Star Wars JK II Jedi Outcast\GameData
8. Click on jk2mp.exe to add it.
9. Click apply and close out of everything.
Launch "Play Star Wars JK II Jedi Outcast" on Start Menu. When program opens, choose Multiplayer. It should now launch.
Proof of Screenshot:
Attachment:
starwars-outcast-mp.jpg