A system boot disk is a floppy disk which allows your computer to boot into an operating system such as DOS. Examples include the DOS installation disk and the Windows 95/98/Me startup disk.
You can use a startup or system disk to clean boot a Windows 95/98/Me computer and you can then run a scan with SWEEP, the Sophos Anti-Virus for DOS emergency command line scanner.
- You should have created a Windows startup disk for your computer during installation.
- If you do not have a startup disk for a computer, you need to boot into DOS. Where possible you should create a startup disk on a similar computer (with the same version of Windows, etc.).
If you do not already have a startup disk for your computer and cannot create one as described in the above paragraph, you will need to create a system disk. You can create a system disk on another computer that is running the same version of Windows.
NOTE: Only carry out this procedure to create a system disk if you do not have a startup disk for your computer.
What to do
Create a properly configured system disk for each operating system you are responsible for. The disk should be created on the operating system that you intend to use it for.
For Windows Me, you must create a Windows 98 system disk, and use this to boot the Windows Me computer.
Create the disk by carrying out the following procedure on a computer that you are sure is not infected:
- Insert a blank floppy disk into the computer.
- Click Start|Programs|MS-DOS prompt, to open a DOS prompt window.
- At the DOS prompt, type
FORMAT A: /S
Where A is the letter of your floppy disk drive.
This formats the floppy disk and copies several operating system files that you will need onto the floppy disk.
- Go back to Windows, and ensure that it is set up to display file extensions.
- Browse to C:\Windows. Copy the file HIMEM.SYS to A:
- Browse to C:\Windows\Command. Copy the following files to A:\
FDISK.EXE, SYS.COM, DEBUG.EXE, SCANDISK.EXE (or CHKDSK.EXE if you have MSDOS 5),
- Using a text editor such as Notepad, create a text file and type the following four lines into it,
FILES = 20
BUFFERS = 4
- Name the file CONFIG.SYS and save it to A:\
- Create another text file. Type the following two lines into the file
- Name the file AUTOEXEC.BAT and save it to A:
- Write-protect the floppy disk and mark it with the name of the operating system it was created for.
Note: If you are using DRVSPACE, DBLSPACE, Stacker, hard disk overlay managers or similar software, you will need additional drivers to access the hard disk.