Loads but won't run

[jlc]

I  have an old dos program and it seems to load with the batch file but will not run, this is the batch file


echo off

cd \hc4

subst b: C:\HC4\acad

hc4.com

subst b: /d

cd\


When I try to run it fails and gives me this message

I/O error 01 PC=3F73
Program Aborted
Bad command or file name

[Jos]

There is no SUBST command in vDos.

Change that to:
USE b: <Windows_path_to_HC4\acad>

These lines could also be deleted:
echo off
subst b: /d
cd\

Jos