If you do not have an MS-DOS boot disk, you can build one if you have Windows 2000:

1. Insert the Windows 2000 CD-ROM in your CD-ROM drive 

2. Open a CMD prompt and type:

    cd /d <CD-ROM Drive Letter>:\VALUEADD\3RDPARTY\CA_ANTIV

3. Insert a 1.44 Diskette in your Diskette drive (A:) and type:


4. After the diskette is created, edit the A:\autoexec.bat file and remove all the lines.

5. Delete the old anti-virus files, leaving:

A:\AUTOEXEC.BAT                              A:\COMMAND.COM                              A:\DRVSPACE.BIN                              A:\HIMEM.SYS                              A:\IO.SYS                              A:\MSDOS.SYS
The above creates a Win95/MS-DOS 7 boot disk.

When you need to boot to MS-DOS, shutdown Windows 2000 and restart with the boot disk in the diskette reader.