Lemmings 1 - Defeating the Copy Protection from the Floppy Disk Release

[CrystalCore]

Courtesy of user McWulff at https://www.dosbox.com/comp_list.php?letter=L&showID=382

For all with the error "Lemmings Disk 1 not found" or "Lemmings Disk 1 Not found, insert into drive A or B and retry":

The Error occurs because of the Copy Protection "keydisk" on the floppy disks. You can handle the Error by editing the file "russell.dat" with a hex editor at your installation folder. The important byte is the first byte 0000. This contains a switch to determine if the "keydisk" check is needed or not. A Value of 09 indicates a floppy check, it the normal value after the first installation.  If you have unexact copies of your Lemmings Disks, the Error occurs. A value of 00 to 08 indicates a "keydisk" check is not needed. To fix the game, use the Hex Editor to change the byte to 00. Fixing this Byte lasts for the the first time you start the game, but each time you run Lemmings, the program adds 1 to this byte, until 09 is reached and the "keydisk" check will then be required again. Run Lemmings once (to get the other bytes correct),then on exit, enter ATTRIB -H +R RUSSELL.DAT at the DOS prompt to make the file READ-ONLY, preventing the byte being updated.

If you do not have a hex editor installed on your operating system, visit Hex Editors for Windows, Hex Editors for Mac, Hex Editors for Linux, or How to Use VIM as a Hex Editor accordingly.

Please note that Linux and MacOS do not have the attrib command, so use the chmod command instead to set the file to read-only:

Code Select Expand

chmod 444 RUSSELL.DAT
The instructions to make RUSSELL.DAT a read-only file will work with Dosbox 0.74-3, Dosbox-Staging, and Dosbox-X.