You need to add some master server addresses to your ut ini file
Open up your UnrealTournament.ini located in /ut99/System and add/edit the following lines to each section
[UBrowserAll]
ListFactories[2]=UBrowser.UBrowserGSpyFact,MasterServerAddress=master.333networks.com,MasterServerTCPPort=28900,Region=0,GameName=ut
ListFactories[3]=UBrowser.UBrowserGSpyFact,MasterServerAddress=master.telefragged.com,MasterServerTCPPort=28900,Region=0,GameName=ut
ListFactories[4]=UBrowser.UBrowserGSpyFact,MasterServerAddress=master.mplayer.com,MasterServerTCPPort=28900,Region=0,GameName=ut
ListFactories[5]=UBrowser.UBrowserGSpyFact,MasterServerAddress=master.qtracker.com,MasterServerTCPPort=28900,Region=0,GameName=ut
ListFactories[6]=UBrowser.UBrowserGSpyFact,MasterServerAddress=master.errorist.tk,MasterServerTCPPort=28900,Region=0,GameName=ut
ListFactories[7]=UBrowser.UBrowserGSpyFact,MasterServerAddress=master.newbiesplayground.net,MasterServerTCPPort=28900,Region=0,GameName=ut
bFallbackFactories=False
[UBrowser.UBrowserMainClientWindow]
bKeepMasterServer=True
Then just like that you will have a working server browser once again
