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Red_Donkey
December 6th, 2019, 10:42 PM
I got this old IBM-DOS (PS2), computer from a friend, if I would help him to get some of the Word Perfect documents off it. I had a hard time working with old diskettes, and instead of deleting files of the diskette, I deleted a library of docs. But this IBM is running an old IBM-DOS ver.3 (I think, Im not at the computer right now), and it doesnt have UNDELETE function. Is there similar undelete-program, that I can install into IBM-DOS ver 3, and recover some of this stuff?

WBST
December 7th, 2019, 06:05 PM
If you haven't done much to the directory structure since, one can even do this via DEBUG. The first character of the filename in the directory is changed to E5h, making the file "invisible", but the remaining cluster info. is often intact and usable (the DOS FAT "high water mark" is where new files are allocated). Any decent hex disk editor would be better than DEBUG however.

Chuck(G)
December 7th, 2019, 06:42 PM
There are a few "undelete" utilities in the SIMTEL20 archive (search it). However, much depends on (1) how fragmented the original file is and (2) what files you've written after the file was deleted. You can retrieve, depending on the above conditions, anywhere from none (file was completely overwritten) to all (contiguous file not overwritten).

I think the older Norton Utilities also have an "undelete" function.

SomeGuy
December 7th, 2019, 06:55 PM
I'd recommend Norton Utilities 4.5. The undelete functionality is built in to the NU.EXE program.

Do NOT copy or write anything to the hard disk until the files are recovered, or you could overwrite data. Run the NU.EXE from the floppy.

Stone
December 7th, 2019, 06:56 PM
I think the older Norton Utilities also have an "undelete" function.4.5 does.

WBST
December 7th, 2019, 07:15 PM
I'd recommend Norton Utilities 4.5. The undelete functionality is built in to the NU.EXE program.

Do NOT copy or write anything to the hard disk until the files are recovered, or you could overwrite data. Run the NU.EXE from the floppy.

If using NU, beware of using other directory manipulation utilities like DS (Directory Sort) to better see which files to undelete. Anything that alters the directory structure will be destructive of existing deleted file information.

Robbbert
December 7th, 2019, 08:31 PM
If you've got another machine with DOS 6, you might be able to put the floppy into that and attempt an UNDELETE. You take your life in your hands though.

If you deleted a directory, then maybe only those utilities mentioned above might work. It's all a gamble as to whether it works, or the data becomes lost forever.