Help with wireless connection please

Are you sure the wireless router you're connecting to is actually the same router that you're connected to when using wire? Is easy to be fooled into assuming it is, esp. if this is a work situation. It's entirely possible you're connecting to some other *internal* wireless router that doesn't have internet access, esp. if when you connect via wireless you see unfamiliar devices! It could even happen at home between neighbors if they both use the default SSID and leave wireless security disabled.

At the momet I'm not sure of anything any longer. I was able to see the laptop in the network on the desktop network but no longer can. I think it is time for me to give up after working on it for many hours and taking it to someone else just hope they can fix it we need it to take on a trip soon   Thanks for your help.