I cant seem to beable to load the original half-life. i get this exact
error upon trying to install the game. C:\
windows\system32\autoexe.nt. the system file is not suitable for
running MS-Dos and Microsoft windows applications.  choose 'close' to
terminate the application. With the options of either closing or
ignoring.  nither chioce matters however.  i have tried running the
install in all of the diferent comadiblitys moads as well.  my grafics
card is a Nvidea 5200 FX if you need to know, also runing with 1.8 Ghz
1.3 Gb of ram.  I am simply looking for a way around this error.  I am
used to finding my way around eroors like this but ass the comming of
half life two has supressed most of the info for the original half
life on the web cant seem to dig up enought info to give me a place to
start.

here you go mate..i got this problem too,

"C:\WINDOWS\SYSTEM32\AUTOEXEC.NT. The system file is not suitable for
running MS-DOS and Microsoft Windows applications, Choose 'Close' to
terminate the application"

There has been a few issues with an error regarding AUTOEXEC.NT. There
is a few simple fixes for this error.

1) Navigate to the REPAIR folder in C:\WINNT or C:\WINDOWS. Copy the
AUTOEXEC.NT file to C:\WINDOWS\SYSTEM32 folder.

2) With the Windows XP CD in the drive, go to Command Prompt and type:
expand (cdrom drive)\i386\autoexec.nt_ c:\windows\system32\autoexec.nt

(cdrom drive) is the letter drive you have your CD-ROM assigned to.
Usually its D:. If it asks you to replace it, click yes.

Microsoft's Support Website has this issue listed and has a similar
approach to fix the issue.

Other files that may be affected are CONFIG.NT and COMMAND.COM. The
procedure is the same for the two files.

Anything else, contact Microsoft.

KuDeTa

edit forgot to add, you can make fixing corrupted windows files easier
with this little app

http://www.visualtour.com/downloads/xp_fix.exe

"This installaton program will reinstall the missing or corrupt
Windows XP system files command.com, autoexec.nt and config.nt. The
absence or corruption of one or more of these files causes a "16 Bit
Subsystem" error.

We recommend that you download this file and save it to your desktop
or to another location where you can find it. Double click on the file
to run it once it's downloaded. If problem reoccurs in the future,
simply re-run this program."

You could just download a new copy of it and replace the old one. Or
load it from the disk. Either way it hsould only take you a minute to
fix.

thanks man that worked well.  lol never thought that the file was
simply missing from the system32 folder. big old DOh! for me.

Try reinstalling the ms dos thing. 
Goto start>run .In the open box type: "cmd". 
at the comand promt, type in the follwing commands and press enter
after each command:
expand CD-ROM drive letter:\i386\config.nt_C:\windows\system32\config.nt 
expand CD-ROM drive letter:\i386\autoexec.nt_C:\windows\system32\autoexec.nt 
expand CD-ROM drive letter:\i386\command.com_C:\windows\system32\command.com 
Exit 

Now try reinstalling. 

Second soln: 
If the above doesn't work... 

In notepda type in: 
dos=high,umb 
device=%SYSTEMROOT%\system32\himen.sys 
files=40 
save the above with name "config.nt". 

now again open a blank document and type the following entries: 
@echo off 
1h %SYSTEMROOT%\system32\mscdexnt.exe 
1h %SYSTEMROOT%\system32\redir 
1h %SYSTEMROOT%\system32\dosx 
SET BLASTER=A220 I5 D1 P330 T3 

save the file as "autoexec.nt". 
Now locate the "config.nt" file and copy it to the %SYSTEMROOT%\system32 folder. 

Do the same with autoexec.nt and command.com and restart..

I ran that visual tour xp fix and it stopped the message coming up,
but now the comp loads for a bit and then stops. I still cant get
halflife to work