Here's how I'd do it. There's 2 methods I see.
1st method
Use 2 different application.
The one at the security desk record the visits and record them in a database.
The one at the boss desk is a background application that check the database for new entry at regular intervals. If there's one, it shows a popup, then put a flag to true.. so that you don't show the alert multiple time.
What's great about this is that you can also record each visit and print reports because you can keep them over time.
2nd method
Use 2 different application.
The application at the boss desk is listening to a specific socket.
On submit, the security application send the info directly to the boss socket.
It's a bit trickier here because some info could be lost on the way, or ip adresses could change. It might be trickier to set up.
Here's some code sample for socket programming. Might not be good, I just googled.
SEND FILE FROM SERVER TO CLIENT USING C# SOCKET PROGRAMMING[
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one example for a popup window
TaskbarNotifier, a skinnable MSN Messenger-like popup in C# and now in VB.NET too[
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