Check:
a) Are you Refreshing from the internet, not 'LAN' or 'Local?' [set ui_netsource 0 for internet, 1 for multiplayer (means nothing for trem), 2 for local etc. but just leave it as '0']
b) Are you refreshing from master.tremulous.net? [sv_master1](If you don't know what I'm talking about, skip)
c) Is your max ping high enough? [setting cl_maxping 9999 will do]
d) Do you have multiple clients open? (I don't think this is true, but people say multiple applications through the same port number causes them to interfere with each other, I'm not sure about the default 1.1 client but the newer ones avoid this issue)
e) Are you connected through a restricted network? i.e. school, workplace etc. (My school prevents private connections so things like msn and IRC won't work)
