I have bought the developer license and a single user license for the Virtual Serial Port Active X Control, and it looks like the biggest mistake of my life. The trial version worked great! But the license keys DO NOT work and I have been three weeks trying to get help. I have tried new computers, other computers, re-installs and un-installs until my fingers are cramped-up. Eltima keeps asking me to do the same thing over and over and over again, and it NEVER works. Now they are not responding at all to my phone calls, emails or IM.

Has anyone EVER got the vspax_single.exe install to actually WORK on Win XP? 

Hello,

We are more than eager to get the details from you on how this problem can be reproduced. Our testers checked you registration keys and confirm that they are valid. I kindly ask you to send us the installation file of your application for investigation.

We will be able to answer to your call during business hours of CET (Central European time) which is GMT + 1 hour. You will be offered to leave a voice mail beyond these hours. Please, note that Note, that we are ready to call back if you have sales questions concerning pricing, licensing and orders. Technical support inquiries including lost serial number issues are not administered by phone, and must be directed via email: mailto:support@eltima.com

I concur that installation is the biggest pain with this otherwise excellent product.  Once you get it sorted out you will be fine.  I suspect that if you are doing the same thing over and over and it's not working, you need to try something different.    Seriously.