Go to |Start| > |Settings| and then along the bottom tap on |Connection|. There should be an option to configure 'Beam'. Tap on it and you will have the option to receive all incoming beams - make sure it is enabled. Check to see if the link 'Receive an infrared beam' helps, situated at the bottom of the 'Beam' page.
However, if you are wanting to dial-up with the mobile phone, go back to the |Connections| tab and then click on the icon 'Connections'. From in here you will be able to manage and create new connections.
Hope this helps.... if it doesn't, just post away!