What is the problem with pointers in c?

I am having a problem with my wireless Internet connection.I will describe it in the comments below. I am looking for a general explanation of the steps that I need to take to fix it. If I get a few pointers, I can sort out the details myself.

• Answer:

  This is not an answer, but some mre details for the question above. I have been connecting to the Internet for years via a cable modem and recently, I upgraded my connection to include a wireless router from my ISP. My ISP set things up a few weeks ago and all was OK until a few days ago. My connection was working and I left my PC for a few hours. When I returned and clicked on Internet Explorer, I got the "white screen of death" saying that Internet Explorer could not connect to the Internet.I checked all cable connectionsand rebooted but to no avail. I phoned my ISP and was told of network problems in my city. However, my friends using the same ISP in the same area had no problems. I contacted my ISP once again and was taken through a series of technical questions. The person answering the phone seemed to be speaking to a Technician in the background and relaying information that he seemed to have limited understanding off. I was eventually told that: "The wireless card on your computer does not match the WPA key encryption" My ISP then advised me to replace my wireless card in my PC. I am reluctant to do this as I suspect that the real problem is that the wrong WPA encryption key has been used somewhere. My ISP disagrees. I am looking for a second opinion as to the meaning of the above technical description of the fault in quotation marks and some general pointers to the steps that I need to take to resolve the problem