Still hoping someone might have some ideas...
It's connecting fairly reliably now and hanging on to the one network, but under properties, it appears the card is sending but not receiving bytes. I had this problem when I first installed the card but had not yet acquired the WEP from the access point upstairs. But now I have the WEP and have tried reentering it, to no avail. I also tried reinstalling the adapter itself, but that didn't help.
I'm connecting to a wifi network with a laptop. The WAP is upstairs (I live in a downstairs apartment, so I can't get closer), and I've always had occasional problems with the signal strength, but even with a low signal, it has functioned. Nothing has changed that I know of, but now it won't connect to the internet or my email server through Eudora, even when it says that there is a good signal. And, alternately, it says no network is available, but when I click on the icon it lists three! (Two of which are neighbors and have never worked.) However, then it won't actually connect--at most I get a tedious serious of little balloons telling me that multiple networks are available without actually being able to connect at all! Have I inadvertantly changed something on my computer? Could it just be some new (hopefully temporary!) environmental interference? How finicky are these things?