Troubles to get into internet via dial up through MS Vista

Hi Gurus and Dudes

just bought a new dell notebook running ms vista (home basic) but having difficulty to get into internet via dial up. Is vista not compatible with dial up ? I've tried two different pre-paid dial up providers, unfortunately, same result, i.e. the internet sharing centre stated internet was connected, however, whenever I clicked the internet explorer icon, it failed to connect and stated no internet connection detected.

I've rung the Dell support service centre and the ISP. They both blamed each other that was not their problem.

Please Please help me out !

Thousand Thanks in advance.