Unable to run Standard Mode Windows with EMM386 (68868)

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
    Microsoft Windows 3.0

This article was previously published under Q68868


When you try to run MS-DOS with Windows 3.0 in standard mode, you receive the following error message:

Cannot run Windows in standard mode;

Check to ensure you are not running other protected-mode software, or run in real mode.
This message occurs if you have installed EMM386.EXE and either expanded memory or UMBs have been allocated by EMM386.EXE. This puts your computer into protected mode, thus preventing you from running Windows in standard mode.


If EMM386.EXE is installed with either the RAM or NOEMS switch to allocate upper memory blocks (UMBs) and DOS=UMB is in the CONFIG.SYS, UMBs have been allocated to MS-DOS.

If you have EMM386.EXE installed to provide expanded memory only and expanded memory is not being used, Windows will turn off EMM386.EXE and run normally. When EMM386.EXE is providing UMB support, or if expanded memory is being used, EMM386.EXE cannot be turned off, so you are no longer able to run Windows in standard mode.

Modification Type: Major Last Reviewed: 5/12/2003
Keywords: KB68868