Setup Does Not Recognize Compaq XMS Device Driver (104734)

The information in this article applies to:
    Microsoft MS-DOS operating system 6.2
    Microsoft MS-DOS operating system 6.21
    Microsoft MS-DOS operating system 6.22

This article was previously published under Q104734


MS-DOS Upgrade Setup does not recognize the Compaq extended memory services (XMS) device driver (EXMEM.EXE). As a result, Setup adds a device command for HIMEM.SYS to the end of your CONFIG.SYS file. When the second XMS driver loads, you receive the following error message:

ERROR: An Extended Memory Manager is already installed.


Setup does not recognize EXMEM.SYS because EXMEM.SYS makes itself look like the MS-DOS HIMEM.SYS driver. Since Setup finds what it thinks is HIMEM.SYS in memory, it determines that it has to update an existing HIMEM.SYS line in the CONFIG.SYS file. When it doesn't find any reference to HIMEM.SYS, it adds a command for it.


To work around this problem, edit your CONFIG.SYS file with MS-DOS Editor and remove the device command for one of the XMS managers.

Modification Type: Major Last Reviewed: 11/18/1999
Keywords: KB104734