Dialup connection window launches randomly

This is caused by some application trying to access the Internet. It is difficult to know which one it is. You may be able to tell if your firewall is warning you of such activity. If that were to happen you could find the application and get rid of it.

A possible solution is to disable the Remote Access Auto Connection Manager Service. Here's how:

Go to Start>> Run. Type in: services.msc [Enter] or click OK.

The "Services" window will now be displayed. In the right pane you will notice an alphabetical listing of the services. Scroll the list to find; Remote Access Auto Connection Manager. Once found, double click it. You will notice a dropdown menu next to "Startup type:" (See Fig. 1). Open this dropdown menu and select "Disable". Click OK to exit. Exit the Services window.

(Fig.1)
Image
Remote Access

It could also be a parasite of some kind trying to access its server to obtain instructions or updates or even to send information that it has gathered. With this in mind, it is better to be safe than sorry, scan your computer with a reliable scanner (or scanners) to keep your valuable information safe. Below is a list of scanners that I recommend and that are free to use.

Adaware SE
AVG Anti-Spyware
AVG Virus Scan