More of a DOS based quesiton than a WinRunner one...
It comes down to the path you have listed including spaces. Dos commands can't handle spaces in paths unless you encapsulate them within quotation marks.
So the command you need to use is:
<font class="small">Code:</font><hr /><pre>
dos_system ("del \"c:\Documents and Settings\henry.txt\"");
You can always trouble shoot DOS commands by actually typing them into the DOS window and seeing the true error message. That would have been a clue as to what you had an issue with. You might have given up a little easy on this one since you had many other outlets to actually test the command [img]/images/graemlins/smile.gif[/img]
Insanity: doing the same thing over and over again and expecting different results