Himem, an extended-memory manager, is a program that coordinates the use of your computer's extended memory, including the high memory area (HMA). It must be loaded before any application or device drivers can use extended memory.

Open the CONFIG.SYS file found in the root directory of your C: drive using Notepad or another text editor (not Microsoft Word or any word processor).

At the top of the file add a line with the text "device=c:\windows\himem.sys" where 'c:\windows' is the path to the himem.sys file.

These changes will take place on the next reboot.

Disclaimer: Modifying the registry can cause serious problems that may require you to reinstall your operating system. We cannot guarantee that problems resulting from modifications to the registry can be solved. Use the information provided at your own risk.