Changing a printers "global default" settings programatically on WinXP

Hi all

Further to my other post I've found some more info on printer settings
specfically

http://support.microsoft.com/kb/140285

I've converted it so that it works in the language I am using (Visual
Dataflex) and it appears to be working in that non of the functions return
errors etc

However having used it to "set" the duplex mode of the printer.

When I go back into "Printers and Faxes" on XP and call up the printers
properties this setting has not changed ?

Should this have worked ? ie am I doing something wrong ?

Or can it not be done this way and I need to use another method ?

Thanks in advance for your help

Andrew

PS I couldn't seem to find an appropraite newsgroup to post this on so I
hope these are the two closest !