How to install MS DOS 1.25 on VirtualBox?

June 1, 2022

List of Files in MS DOS 1.25 on VirtualBox

In the last tutorial, we saw how to install MS DOS 1.25 on MAME. In this tutorial, we are going to install MS DOS 1.25 on VirtualBox. If you want an introduction to MS DOS 1.25, I suggest you to read the first few paragraphs of our post how to install MS DOS 1.25 on 86Box.

You need to download the following file to follow this tutorial:

MS DOS 1.25 CDP OEM archive

MS DOS 1.25 was not sold as a retailed package. It was only available to OEMs. In this tutorial we use the Columbia Data Products OEM that works well on IBM PC clones.

Creating the Virtual Machine

If you have not already installed VirtualBox, you can download and install it from its website. On Linux, you can also install it from your distribution's repositories or other third-party repository for your distribution.

Open VirtualBox, and click on New Machine. The new machine dialog box will open:

Enter the name of the VM as you wish and make sure the Type is set to Other and Version is set to DOS. Click on Next > to continue.

4 MB or memory is much more than enough for this VM. Set it and click on Next >.

This version of DOS does not support hard disks, so click on Do not add a virtual hard disk and click on Create button.

You will be warned that there is no hard disk. Click on Continue. Now the Virtual Machine is created. Extract the MS DOS 1.25 archive you downloaded from above and open the extracted folder. Go to the images folder inside it and copy the file called CDPDOS.IMG to the VM folder.

Back on the VirtualBox window, click on Empty that is written in front of Floppy Device 0: (See the above image). Now click on Choose a disk file ... and choose the CDPDOS.IMG image (You may need to choose All Files from the bottom right corner of your file chooser to see the disk image file).

Now click on Start to start the virtual machine:

When asked for Date and time, just press enter. Do not enter anything. MS DOS 1.25 has problems with dates later than year 2000, so it is best to leave the default date set. You can enter the DIR command to see the list of files:

List of files on MS DOS 1.25 on VirtualBox

You can now close that window. When you will try to close the window this window will open:

Make sure to choose to Power off the machine and then click on OK.

Since MS DOS 1.25 is used from floppy disks, it is better to add another floppy drive as it is the required setup for many software and more convenient with others. Click on Settings and choose storage from the left sidebar. Now click on the small floppy icon next to Controller: Floppy to add a floppy drive (see the below image):

Click on Leave Empty when the following window opens:

Now click on OK to close the settings window. Now we can add another floppy if we want and it will show up as B:.

That's it. We used MS DOS 1.25 in VirtualBox. Read the manual linked below to learn more about MS DOS 1.25. Also read the manuals which I will post with the IBM PC DOS 1.10 tutorial because they are more detailed and MS DOS and PC DOS are almost same at this stage.