# Installing a game expansion or add-on

Some MS-DOS games received official expansion packs: these usually came on their own diskettes or CD-ROMs and require separate installation. To install an expansion:

1. Launch the original game and then quit back to DOS. Leave the window open at the DOS prompt.
2. - If the expansion is on a physical CD, insert the CD into your Mac’s DVD drive.
   - If the expansion is on a disc image, double-click the disc image to mount it as an OS X volume.
3. Browse the expansion’s files in Finder to locate the installer program for the expansion: usually “INSTALL.EXE”, “SETUP.EXE” or similar.

4. Drag the expansion’s installer program into the DOS window to launch it. Follow the installer’s instructions to complete the installation.

   If the installer asks for the location of the original game, enter the path on drive C in which the original game was installed: e.g. “C:\GAMENAME”. If you’re not sure, choose the installer’s default location if it has one, or browse the gamebox in Finder to locate the game’s folder.

5. If the expansion came on a physical CD or disc image, it may have copy protection that requires the expansion CD to be present while playing. If so, import the expansion CD into the gamebox after installation.

   While playing, you can use Drives ▸ Next Disc to switch from the original CD (if any) to the expansion CD.

### Further reading

- Applying a patch or crack