You guys totally missed the point. Delete adapter blah-blah-blah - it's NOT the problem with the wireless adapter. The virtual adapter also has NOTHING to do with this.
He is connecting with real physical adapter to the wireless network, say "linksys", but Windows 7 gives it a name "linksys 2" and if you connect to it tomorrow it will be "linksys 3" and so on. It's the name of network that changes, not the adapter. This is the software problem, windows somehow treats a known hotspot as a different one.
My guess is it's somewhere in the registry, if you search hard enough, you can find where windows saves hotspots to which it connected before. Also check if your provider has multiple hotspots, it may connect to a different hotspot with the same SSID, so windows gets confused and assignes some weird numbers to differenciate.