While a bit technical, the following simplified explanation is essential to understanding both the problem and the solution. You need to understand what is involved to determine how to resolve the issue satisfactorily. These assume you are using a workstation rather than a server as your hardware platform.

Which solutions apply to your personal circumstances depend upon both hardware and software considerations. It also applies to Operating Systems (OS) that are acting 'Windows-like', such as the Apple MacIntosh with OSX and Unix style platforms using 'WINE'. This article attempts to explain some of the complexities behind this issue as well as how the fix needs to be accomplished and what the limitations are, depending upon the combination of your version of Windows and hardware. (Games written specifically for 64-bit systems have a much, much larger memory limit.) It is possible for the player to make some relatively simple changes to their Windows configuration to enable their 32-bit game to access up to 4GB of Random Access Memory (RAM), assuming at least that much is installed. Most games that are written for Windows are '32-bit' by default, and as such are limited by Windows to having access to only 2 Gigabytes (2GB) of system memory (not video memory, which is separate). 5.5 Page File Size and The Commit Limit.