[nfbcs] Network info inconsistency

[Tracy Carcione]

Please riddle me this:
Last night, my netbook wouldn't connect to my wireless network.  It said
"limited or no connectivity".  But, when I went to the Control Panel,
Network Connections, and View Available Networks, there was my network
"signal strength excellent; connected".
So, why does one part of my netbook say I'm connected, and the rest say
not?  (And it really appeared to be not.)  And how can I figure out the
cause of not connecting?
And can anyone recommend a source for learning about this kind of thing,
quick and dirty?  I'm not terribly interested in all the details, but I do
want to be able to fix my own darn connection when it doesn't work. Is
there some helpful book, or something like that?
I'm running XP on my netbook.
Thanks.
Tracy