EMM386 May Not Provide LIM 3.2 Support (80874)

The information in this article applies to:
    Microsoft MS-DOS operating system 5.0
    Microsoft MS-DOS operating system 5.0a
    Microsoft MS-DOS operating system 6.0
    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 Q80874


When EMM386.EXE is installed using both the Pn= (where n is an integer between 0 and 255, inclusive) and RAM options, the following warning message is displayed:

WARNING: EMM386 installed without a LIM 3.2 compatible Page Frame

Press any key when ready...
This message indicates expanded memory is being provided in accordance with the Lotus/Intel/Microsoft (LIM) 4.0 Expanded Memory Specification (EMS), however, the inability to set a 64-kilobyte (K) contiguous page frame is preventing EMM386.EXE from providing LIM 3.2 compatible expanded memory.


On some 80386 machines, the upper memory area (UMA) can become fragmented by the presence of ROM BIOS extensions, video RAM, and so forth. If EMM386.EXE cannot find 64K of available contiguous RAM in the UMA, it cannot establish a page frame. In such cases, the Pn= option can be used to allocate a partial and/or noncontiguous page frame in 16K segments.

For example, EMM386.EXE can be used to install a noncontiguous, 64K page frame with four 16K segments at C800, CC00, D800, and DC00 by using the following command in the CONFIG.SYS file:
   device=c:\dos\emm386.exe P0=C800 P1=CC00 P2=D800 P3=DC00 RAM
Alternatively, a 16K segment, or partial page frame, can be installed at DC00 using the following command in the CONFIG.SYS file:
   device=c:\dos\emm386.exe P0=DC00 RAM
Note that both of the above examples provide expanded memory in accordance with the LIM 4.0 EMS. Applications requiring LIM 3.2 EMS may not be able to recognize or use this EMS.


Microsoft MS-DOS "User's Guide and Reference," version 5.0, pages 605-609

"Lotus/Intel/Microsoft Expanded Memory Specification" (available free from Intel)

Modification Type: Major Last Reviewed: 5/10/2003
Keywords: KB80874