You may get this error while using your USB modem or your wireless USB if your dialup connection is missing /deleted or there is no phone number in the dialup. Click on "start" at the bottom left corner of your computer screen and select "Connect to" and select "show all connection" on XP or "show all" on Vista. If you do not see connect to then go to control panel and select network connection in XP or network and sharing center in Vista. You will see all the connections that are created for your modem. If the connection for your USB modem is missing or deleted then create a new connection (refer to how to create a dial-up for XP or Vista with screenshots in the content page). If you see the connection, right click and select properties. Make sure to uncheck “use dialing rules” and make sure that the phone number is present (for USB modems, wireless USB modems or 3g USB modems the dial-up number is *99# unless specified by your internet service provider). Also make sure that you have selected the correct modem from the list under the general tab.