network adapter

[clarad]

I changed yesterday to BT and my computer a HP pavillion dv 2500 works fine with ethernet cable but not with wireless. After very patient BT man it took 3.5 hours to tell me that it was my network adapter and that I should contact my supplier. Now is that Hewlett Packard, and is this a software problem my system is using Vista and is 2 years old, or do I need to purchase hardware, not sure what a network adapter is. Thank you