Hello. This "server refresh" problem only fixes itself when I restart Half-Life.
Scenario: I'll go to the server selection window in Half-Life and I'll refresh fine - all the servers show up. Then i'll push "refresh" again for an update and the list will be down to only about 10 servers. I push "refresh" one more time and now I see NO SERVERS at all. My internet connection is still very active, and restarting Half-Life usually fixes the problem. But this happens very very often. If anyone else is having a similar problem what's the fix?