There are a wide variety of reasons you should not use the Steam or GOG Jedi Knight and Mysteries of the Sith installations. There are a lot of problems with both. 

  • Steam and GOG use a modified JK.EXE that is not compatible with community patches required for Jedi Knight Enhanced, Jedi Knight Rebirth, and the JK Unofficial Patch.
  • Steam is missing the original game soundtrack and the joystick profiles.
  • Steam and GOG do not provide the required DirectPlay registry keys to play Jedi Knight and Mysteries of the Sith on DirectPlay gaming services such as Voobly or GameRanger.
For a detailed comparison of the original games and the Steam and GOG release, please visit this link.
Detailed File Comparison - JK 1997 OEM, Steam, GOG, and 64-Bit Installations
http://jkdf2.com/articles/12-detailed-file-comparison-jk-1997-oem-steam-gog-and-64-bit-installations

If you already have the Steam or GOG Distributions of these games, please follow these guides to uninstall: 
The remaining instructions in this guide apply only if you have uninstalled your Steam or GOG versions of Jedi Knight and Mysteries of the Sith.

We provide original distributions of both Jedi Knight and Mysteries of the Sith in .ISO (Disc Image) formats. These are the original 1997 and 1998 distributions of both games. 

How to Install Daemon Tools to Mount Jedi Knight Disc 1, Disc 2, and Mysteries of the Sith ISO Files for installation with the 64-Bit Installer

Step 1 - Download Daemon Tools Lite to mount the ISO files as virtual discs: http://jkdf2.com/files/DTLite501-0406.exe



FIGURE 1 - First setup page. Select language and click Next to continue.



FIGURE 2 - Choose Personal License, and click Next.



FIGURE 3 - Click Next, and then click "Free License". This screen is slightly misleading.



FIGURE 4 - Click Next.



FIGURE 5 - Click Next.



FIGURE 6 - Installation in progress.

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FIGURE 7 - Daemon Tools Virtual Disk Driver Installation. Check "Always trust software..." and click Install.




FIGURE 8 - Installation complete. Uncheck "Run DAEMON Tools Lite" and click Finish. DAEMON Tools will now be associated with all .ISO files on your computer.

Simply double click any .ISO file on your computer to mount it as a Virtual Disc.