How to configure memory for a PC-DOS 2000 guest operating system

This article describes how to configure memory for a PC DOS 2000 guest operating system.

Note Because there are several versions of Microsoft Windows, the following steps may be different on your computer. If they are, see your product documentation to complete these steps.

For most DOS programs, you must have a certain amount of free conventional memory. Conventional memory is the first 640 KB of memory. Conventional memory is most critical when you are running a DOS program. With DOS memory management, you must use more configuration to obtain optimal free conventional memory.

To obtain optimal free conventional memory in the IBM PC DOS 2000 guest operating system, follow these steps:

1. Click Start, point to Programs, and then click Connectix Virtual PC.
2. In the Virtual PC dialog box, select the PC DOS 2000 guest operating system from the list, and then click Start Up.
3. In the guest PC, type e config.sys at the command prompt, and then press ENTER.
4. In the PC DOS 2000 editor, type the following configuration:
   DEVICE=C:\DOS\HIMEM.SYS
   DEVICE=C:\DOS\EMM386.EXE NOEMS I=B100-B7FF I=C600-C7FF I=CC00-DFFF I=E600-EFFF
   DEVICE=C:\DOS\SETVER.EXE
   DEVICEHIGH=C:\CNTX\CDROM.SYS /D:IDECD001 /L:E
   DOS=HIGH,UMB
   FILES=30
   BUFFERS=10
   LASTDRIVE=Z
5. Press F2 to save.
6. Press F3, type e autoexec.bat at the command prompt, and then press ENTER.
7. In the PC DOS 2000 editor, type the following configuration:
   @echo off
   SET BLASTER=A220 I5 D1 H5 T6
   PROMPT $p$g
   PATH=C:\DOS;C:\CNTX;
   LH C:\DOS\MSCDEX.EXE /S /D:IDECD001 /L:E
   LH C:\DOS\SMARTDRV.EXE
   LH C:\CNTX\FSHARE.EXE /L:1
   REM C:\CNTX\IDLE.COM
   SET TEMP=C:\DOS
   LH C:\DOS\MOUSE.COM
   LH C:\DOS\DOSKEY.COM
8. Press F2 to save.

Note With the configurations in steps 4 and 7, the PC DOS 2000 guest operating system has 632,928 bytes or 618K free conventional memory. PC DOS 2000 is only included with the retail version of Virtual PC 5.x. The trial version of Virtual PC, certain volume license versions of Virtual PC, and Virtual PC 2004 do not include PC DOS 2000.

For additional information about PC DOS 2000 memory optimization, visit the following IBM Web site: For additional information about how to edit a file in PC DOS 2000, click the following article number to view the article in the Microsoft Knowledge Base: For additional information about how to install the PC DOS 2000 guest operating system, click the following article number to view the article in the Microsoft Knowledge Base: