Hi kawaad,
The only aspect of Windows Vista that has been known to cause conflicts with the Auctiva software is the Live Toolbar that is enabled be default, although I've never heard of it causing this specific problem. If this toolbar is enabled on your Vista system, it's definitely worth a shot to re-enable it and see if that alleviates this problem.
Any additional questions or concerns? Please feel free to contact our customer support team using the appropriate link on our help page: http://www.auctiva.com/free-auction-software-help/help.aspx
-Mike