If you haven't found anything else yet, you could get
BCWipe.
It is a file shredding/disk wiping application.
It's the trial, but it should work.
It is a file shredding/disk-wiping application.
This will definitely, purge all of the
cluster-chains, the areas on the HD where the files are stored.
When you delete a file within
Windows, it will usually only delete the file header, leaving the main body/data of the file intact,
residing in the
cluster-chains, which could possibly be recovered, by using file recovery applications.
There are also many free file shredding applications available, just Google for file shredders.
They describe using
BCWipe, as a 'Military Grade' procedure.
It not only shreds files, but wipes the free space/swap file etc on the HD as well,
so for example, you could wipe the free space on the drive, after you 'delete with wiping,' the files.
The more passes, the less chance of it being recovered, bearing in mind , the old DoD standard is the 7 pass character rotation wiping,
and this app goes up to 100 passes, or maybe more, which would not really be necessary though and would really take ages.
NOTE: - I couldn't see any indication of file size on their page, but if it is too large for a floppy,
you could always get a free file splitting/joining application from somewhere, if you can't find a small enough shredding appplication to fit on a floppy.
Download here:
http://www.jetico.com/wiping-bcwipe/
A 30 day trial though, It's lucky I got my version, full, ages ago.
There is also another free application here:
http://www.fileshredder.org/
Note: - This application is only 1.15 MB, so will fit on a floppy,
but I'm not sure if this application will wipe the free space on the HD as well.
The original
BCWipe did do that and it was about 800 KB in size.
There are very many more, if you Google for them, you will see them.
Hope it helps.