The himem.sys is a driver file first included with MS-DOS 5.0 and included with Windows up to Windows 98 that manages extended memory. Versions of Microsoft Windows after Windows 98 only utilized the memory manager included with Windows. To load the himem.sys, add the following lines into your config.sys.

DEVICE=C:\Windows\HIMEM.SYS DOS=HIGH,UMB DEVICE=C:\Windows\EMM386.EXE NOEMS

EMM386.EXE, Extended memory, Memory terms

  • Himem.sys missing or corrupt.
  • How to get old MS-DOS games to run in Windows.
  • Information on the autoexec.bat and config.sys, including how to load the himem.sys.
  • Memory (RAM) help and support.