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#132947 - 2005-01-25 01:17 PM Disabling the f8 key.
Stephen Wintle Offline
Seasoned Scripter

Registered: 2001-04-10
Posts: 444
Loc: England
Hi,

I work in a school (with many naughty pupils) and I want to be able to take the ability away for pupils to be able to use the 'f8' key during bootup. I have searched and found a few referals to a ntldr file 'ntldrnof8', however this file seems to stop my machines booting up altogether. I use windows 2k clients can anybody help?

Regards

Steve.
_________________________
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#132948 - 2005-01-25 02:54 PM Re: Disabling the f8 key.
Les Offline
KiX Master
*****

Registered: 2001-06-11
Posts: 12734
Loc: fortfrances.on.ca
A member with 353 posts should know by now that the scripts forum is for posting scripts, not to shop for them. Please post in the Starters or General forum.
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Give a man a fish and he will be back for more. Slap him with a fish and he will go away forever.

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#132949 - 2005-01-25 03:37 PM Re: Disabling the f8 key.
AzzerShaw Offline
Seasoned Scripter
****

Registered: 2003-02-20
Posts: 510
Loc: Cheltenham, England
Hi,

I wouldnt think it would be that much of a problem if they did. I guess its annoying when it boots up in safe mode but thy still need to logon.
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If at first you don't succeed, try again. Then quit. There's no use being a damn fool about it. - W.C Fields

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#132950 - 2005-01-25 03:55 PM Re: Disabling the f8 key.
Sealeopard Offline
KiX Master
*****

Registered: 2001-04-25
Posts: 11164
Loc: Boston, MA, USA
For those who love Assembler or are loving IT way to much, here's the solution:
Quote:


I got it! I needed the same thing, did some spelunking and found that ntldr
does the F8 checking & displays the troubleshooting menu. Since ntldr is
pretty small and can only use BIOS INT 16 for keyboard input, it was pretty
easy to look amongst all the INT 16 (keyboard handler) byte sequences in
there (there were only three). I found this one at offset 085A:

MOV AX,0100
INT 16 ;Checks if keystroke waiting in buffer, ZF=0 if yes, ZF=1 if no
JNE 09 ;Jump ahead nine bytes if ZF=0

By just replacing the JNE 09 with three NOP's (no op, byte code 90), I
disabled execution of the keyboard input handling, so no more response to F8
key press. If you want to check for yourself, load ntldr into your assembly
editor and search for "CD 16" hex string. You'll find three; this one's the
second.

If you don't want to fuss with doing yourself, I've put a copy of my ntldr
on our ftp site at skykomish.lib.washington.edu in the "Public" folder with
the name "ntldrNOF8" (log on as "anonymous"). In this version, I also
replaced the "press f8 for troubleshooting" text (found at bottom of ntldr)
with <space> characters so that users don't see the F8 prompt.

Mike Reynolds
Univ of Washington





Source: http://groups-beta.google.com/group/microsoft.public.win2000.security/browse_thread/thread/4db76c0cf6d216be?hl=en&
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There are two types of vessels, submarines and targets.

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#132951 - 2005-01-25 03:59 PM Re: Disabling the f8 key.
Jochen Administrator Offline
KiX Supporter
*****

Registered: 2000-03-17
Posts: 6380
Loc: Stuttgart, Germany
But Stephen said :

Quote:

I have searched and found a few referals to a ntldr file 'ntldrnof8', however this file seems to stop my machines booting up altogether.


_________________________



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#132952 - 2005-01-25 04:00 PM Re: Disabling the f8 key.
Les Offline
KiX Master
*****

Registered: 2001-06-11
Posts: 12734
Loc: fortfrances.on.ca
We lock down machines using Fortres.
_________________________
Give a man a fish and he will be back for more. Slap him with a fish and he will go away forever.

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#132953 - 2005-01-25 04:09 PM Re: Disabling the f8 key.
Sealeopard Offline
KiX Master
*****

Registered: 2001-04-25
Posts: 11164
Loc: Boston, MA, USA
I'd hack the NTLDR myself and not rely on somebody else's hack. It could be a mismatched NTLDR file which would explain the stopping of the boot process.
_________________________
There are two types of vessels, submarines and targets.

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