Top 50 DOS Problems Solved: Shrinking Hard Disk

Q: My hard disk seems to be getting smaller! There is a megabyte less free space than there was a month ago, yet I have not saved anywhere near 1MB’s worth of files. What’s going on?

A: This is quite a common problem, but most sufferers don’t realise they’ve got it. What happens is that some of the free space gets allocated to a non-existent file.

In other words the disk filing system has, in your case, a megabyte allocated to one or more files that don’t have a directory entry. They cannot therefore be seen with the DIR command, nor deleted.

Fortunately it is possible to turn these lost chains, as they are called, back into real files which can then be seen and deleted in the normal way. Simply type this command:


If you have any lost chains, Chkdsk will tell you so and ask you if you want to convert them into files. Answer ‘Y’.


One thought on “Top 50 DOS Problems Solved: Shrinking Hard Disk

  1. interesting enough, I had somebody come to me the other week with a broken SD card with quite important videos from a conference on it.

    They had done a check disk, which recovered the .chk files and of course this overwrote any chance of me using Recuva to get the files back.

    Luckily, renaming the .chk files to .mp4 got them back, but I remember years ago that the .chk files were just garbage.

    Thanks for these blog posts, I find them very amusing!