How to create an Msdos.sys file larger than 1024 bytes (129998)

SUMMARY

Some programs expect the Msdos.sys file to be at least 1024 bytes in length. If it is not, these programs may not work correctly. For example, if an anti-virus program detects that the Msdos.sys file is less than 1024 bytes in length, the program may assume that the Msdos.sys file is infected with a virus.

If you use the SYS command to transfer system files from your Windows Startup disk to the hard disk, the Msdos.sys file that is copied to the hard disk is less than 1024 bytes in length. This article describes how to create an Msdos.sys file that is at least 1024 bytes in length.

MORE INFORMATION

To create an Msdos.sys file that is at least 1024 bytes in length, follow these steps:

At a command prompt, type the following lines, pressing ENTER after each line:
attrib -s -h -r c:\msdos.sys
edit c:\msdos.sys

Add the following lines to the Msdos.sys file, where <Windows> is the folder containing Windows (for example, C:\Windows). If you are using disk compression software (such as DriveSpace), change the letter in the "HostWinBootDrv=" line to the letter of the host drive.

   [Paths]
   WinDir=<Windows>
   WinBootDir=<Windows>
   HostWinBootDrv=C

   [Options]
   BootGUI=1
   ;
   ;Some programs on this system expect the Msdos.sys file to be at least
   ;1024 bytes in length; hence, the following lines create an Msdos.sys
   ;file that is greater than 1024 bytes in length. These lines are not
   ;needed for Windows to boot or run.
   ;xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxa
   ;xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxb
   ;xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxc
   ;xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxd
   ;xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxe
   ;xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxf
   ;xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxg
   ;xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxh
   ;xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxi
   ;xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxj
   ;xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxk
   ;xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxl
   ;xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxm
   ;xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxn
   ;xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxo
   ;xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxp
   ;xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxq
   ;xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxr
   ;xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxs

You must add the lines with all the Xs to make the Msdos.sys file at least 1024 bytes in length.

Save the Msdos.sys file, and then exit Edit.com.
Type the following line, and then press ENTER:
attrib +s +h +r c:\msdos.sys
Restart your computer.

For additional information about how to determine which folder Windows is installed in, click the following article number to view the article in the Microsoft Knowledge Base:

305792 How to determine which folder Windows is installed in