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This step-by-step article describes how to install Virtual Machine Additions to provide additional functionalities such as Shared Folders in an MS-DOS-based virtual machine in Microsoft Virtual PC 2004.
DOS Virtual Machine Additions (Dos Virtual Machine Additions.vfd) are included with Virtual PC 2004 and are located in the following folder on the Virtual PC 2004 CD-ROM:
CD-ROM Drive Letter:\Additions
To install DOS Virtual Machine Additions to an MS-DOS-based virtual machine, follow these steps:
Start the MS-DOS-based virtual machine, and permit it to finish starting.
In the host operating system, open the CD-ROM Drive Letter:\Additions folder.
Drag the Dos Virtual Machine Additions.vfd file from the CD-ROM Drive Letter:\Additions folder to the floppy disk icon in the lower left corner of the virtual machine window.
In the virtual machine window, type a:\dosadd.bat, and then press ENTER.
After the Dosadd.bat file has finished loading, you receive the following message:
You have successfully installed DOS Virtual Machine Additions. Please eject the DOS Virtual Machine Additions virtual floppy disk and restart the virtual machine.
Verify that the Config.sys file contains the following line:
If this line does not appear, edit the Config.sys file to add the line. This line allows Shared Folder functionality in the MS-DOS-based virtual machine.
Note For CD-ROM access in an MS-DOS environment, the Mscdex.exe file is also required.
For additional information about how to access CD-ROM drive from MS-DOS, click the following article number to view the article in the Microsoft Knowledge Base:
135174Cannot access CD-ROM drive from MS-DOS mode or command prompt
DOS Virtual Machine Additions can be installed on any MS-DOS-based virtual machine. DOS Virtual Machine Additions installs the following files:
Fshare.exe - Makes it possible to use shared folders between your MS-DOS-based virtual machine and the host operating system.
Cdrom.sys - Provides support for the Virtual PC 2004 emulated CD-ROM drive.
Idle.com - Allows Virtual PC 2004 to detect when an MS-DOS-based virtual machine is idle or inactive and to automatically cycle down CPU usage on the physical computer.
Mouse.com - Provides mouse functionality.
These four files are installed in the VMADD folder on drive C of the virtual machine. The Autoexec.bat and the Config.sys files are modified to use these new files.