long delay when invoking any web service the first time

[bdtmike]

I'm using VS2005 and creating a VB.Net Winforms app.
The app uses a couple of web services.
For some reason, when I start the app, there is a 30 second delay when
VB invokes its first web service. After that, the response time on
subsequent calls is nearly intantaneous. As an example, If I'm
debugging and press <F5I'll get the 30 second delay on first
invocation, then it's fast after that. If I stop the program and
restart (F5), I get the same thing.

To isolate the problem, I created a simple vb.net app with 4 buttons
where all they do is invoke the HelloWorld function on 4 different
servers. Turns out that no matter what server I hit, I get that big
delay the first time.

I also wrote an analagous tester app using Excel and the SOAP
toolkit. This exhibits no long delay--its instantaneous.

Further, I copied my VB app over to another PC with VS2005 installed
and had no delay.

Any ideas what this might be?