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B.M.
01-02-2007, 05:42 PM
Way back in June 2003 b1naryb0y told us how to hide a folder using the Ren Alt255 facility in DOS. The system has worked well all this time but all of a sudden has stopped working and I canít get into my Private folder.

I thought I must have stuffed up my rename but Iíve found that having made a test folder I canít hide it using Alt255 to rename it.

Iíve tried from the DOS prompt in WinME which used to work and Iíve tried from DOS off a WinME start-up Floppy and a Win98 start-up floppy. No luck, but a message

ďRequired Parameter MissingĒ

Any DOS guys out there with any ideas?

Got me licked. :o

pctek
01-02-2007, 06:25 PM
Sure you didn't just make a mistake with the renaming?

http://dos.rsvs.net/DOSPAGE/DEBUG.HTM

B.M.
02-02-2007, 06:40 AM
Sure you didn't just make a mistake with the renaming?

http://dos.rsvs.net/DOSPAGE/DEBUG.HTM

Positive I didn't make a mistake with the renaming.

I can't even Rename a new test folder.

However that's an interesting link you provided. Good old DOS aye. :thumbs:

Graham L
02-02-2007, 01:38 PM
The Alt/ thing needs the Num Lock key on, I think. If it's off, you don't get the appropriate code. :)

B.M.
02-02-2007, 08:37 PM
The Alt/ thing needs the Num Lock key on, I think. If it's off, you don't get the appropriate code. :)

Dead right Graham, and the Number Keyboard must be used as opposed to the top row, but nooop, no joy.

I canít believe I canít even get it to hide a new folder.

Another setback is my other computer runs XP and thatís little better than useless when it comes to DOS. :rolleyes:

Graham L
03-02-2007, 12:44 PM
It's a legacy thing, dating from the fixed 8.3 file (and directory) naming. The NUL character 0x00 which is what you get from Alt/000 was an illegal character in names. Such names are invisible because they are like the names of deleted files.

This new (mis)behaviour is likely to have come from a change ("improvement") in the keyboard entry routines,which eliminates the NUL before it's passed to the command processor.


Are you trying to rename the directory so you can access the files?

You might be able to do this by creating a file in Notepad called, say FIXIT.TXT containing the command line: e.g.
rename C:\[NUL]thename C:\thename
Did it work?

Echo will display it on the screen, but it will also pass it to the command processor, and it doesn't go through the keyboard entry routines.

(You should be able to use the Alt/000 scheme in Notwead, but if you can't, use the character set cut/paste ... the very first "character" displays as a space, but has to be 0x00).

Then in a DOS window, echo FIXIT.TXT


This is not guaranteed to work, but it should be OK in real DOS or WinME. I don't know how XP would behave.

Graham L
03-02-2007, 01:49 PM
P.S. It's so long since I've done anything like this ... I think you need to do echo < FIXIT.TXT. That would mean ... "run the echo command, giving it input from the file". The original line I gave would just type the filename. Not useful ;(

B.M.
03-02-2007, 02:14 PM
Thanks Graham Iíll give it a go. :D

I thought it might be the keyboard but changing that changed nothing. :rolleyes:

The ďRequired ParameterĒ missing definitely comes somewhere within ďAlt255Ē

Speedy Gonzales
03-02-2007, 02:39 PM
Are u talking about this (http://governmentsecurity.org/archive/t8137.html)

open explorer
new dir
f2
alt255 hiddendosdir

under dos can't be accessed

This works, I just tried it. Opened up a prompt and cd to the hdd.

The folder I tried it on doesn't appear.

By the looks of it u don't do it in DOS. You do it in my computer.

B.M.
03-02-2007, 04:17 PM
Are u talking about this (http://governmentsecurity.org/archive/t8137.html)

open explorer
new dir
f2
alt255 hiddendosdir

under dos can't be accessed

This works, I just tried it. Opened up a prompt and cd to the hdd.

The folder I tried it on doesn't appear.

By the looks of it u don't do it in DOS. You do it in my computer.

Yep, thatís what Iím talking about Speedy. :thumbs:

The file is already there and been named. It appears in Explorer as a (Underscore) _ registering 0 bytes. (Even though itís about 200k)

It has worked brilliantly for over 3 years and has been hidden and un-hidden umpteen times.

Yep, the folder can be made via explorer but is hidden and un-hidden in DOS.

I havenít got Grahams idea to work yet but I havenít given up yet. :D

Graham L
04-02-2007, 02:11 PM
Of course, in my suggested file, "[NUL]" indicates that you should put the code (0x00) produced by Alt/000 (or from the character set) at that point, not that particular sequence of charcters. The command interpreter and the file structure don't know about such things. ;)

Also the second line is just "anything" to ensure that the command in the first line is terminated with a carriage return, so that it will be executed by the command interpreter. The second line will be echoed, with an error message because it won't be recognised as a command. You could make it "echo This is tidier". That when echoed by your echo command will invoke the echo command again to write it out, rather than the command interpreter echoing it and trying to execute it.

All clear? :D :cool: :thumbs:

B.M.
04-02-2007, 02:23 PM
Of course, in my suggested file, "[NUL]" indicates that you should put the code (0x00) produced by Alt/000 (or from the character set) at that point, not that particular sequence of charcters. The command interpreter and the file structure don't know about such things. ;)

Also the second line is just "anything" to ensure that the command in the first line is terminated with a carriage return, so that it will be executed by the command interpreter. The second line will be echoed, with an error message because it won't be recognised as a command. You could make it "echo This is tidier". That when echoed by your echo command will invoke the echo command again to write it out, rather than the command interpreter echoing it and trying to execute it.

All clear? :D


Ahhhheeeeeemm, of course I understand. :blush:

Perfectly clear! :dogeye:

(thinks out loud thereís a 1 or a 0 missing somewhere and I think I might be the 1) :D

B.M.
09-02-2007, 06:46 AM
Another really odd one this.

The good news is I recovered all my files from my Alt255 Secret folder by removing the HDD and fitting it in an old P3 computer. :thumbs:

After Windows discovered all sorts of new Hardware I went straight to the DOS prompt and un-hid the folder the same way as Iíd done it many times before.

It seems to me the HP P4 1600mhz machine wonít recognise the ďAlt255Ē Command in DOS.

Real odd.

Anyway, thanks to all who tried to assist. :thumbs:

The immediate problem is how to hide, or password protect, a folder using XP as the Alt255 DOS Command doesnít seem to work with XP. Seems later version Hardware as well as XPís reduced DOS functions may be a factor. :confused:

TGoddard
13-02-2007, 09:18 PM
I think you can set the folder to hidden in the properties menu. If you want to keep files safe properly I would highly recommend TrueCrypt ([url]http://www.truecrypt.org/[/url). This allows you to create a virtual drive, the contents of which is stored in an encrypted file. Encryption is the only way to non-trivially protect files you want to keep secret.