If the dial-up connection dialog keeps coming up automatically while working, this is caused by some application which is trying to connect to the internet. Numerous applications are configured or designed to check for updates automatically by contacting their home page. Some applications notify the user before contacting their servers, others don't. Adware and other parasites also contact their servers to fetch Ads and some Trojans may even send out your valuable information.

To prevent the dialup box automatically activating , turn off the "Remote Access Auto Connection Manager Service". This Service creates a connection to a remote network whenever a program references a remote DNS or NetBIOS name or address. To disable this service, use these steps:

1. Right click My Computer icon,
   choose "Manage" > "Services and Applications" > "Services"
    
2. In the right pane,
   select  "Remote Access Auto Connection Manager" and double click
    
3. In the General tab, use the "Startup type" drop box and choose Disabled.