Instead of trying to join servers from http://www.ace-spades.com/play (because when you click on the links, you get the error)
Go to http://aceofspadeswiki.com/index.php?title=Server_Browsers.
These browser lists connects to the master server list (http://www.ace-spades.com/play is the master list...i think). PLEASE NOTE that this browsers are USER CREATED and are THIRD PARTY, meaning AOS staff did not create this.
-AOS WikiCurrently the game's official page has an extremely basic server list with no sorting abilities.
Some users have set about creating third party server browsers in order to introduce more functionality.
I suggest using Spadille (You just need to double click to join server) Spadille is windows only (sorry Macs, you're missing out.)
MAC USERS you have to use "5 of Diamonds". That is the only browser compatible with Mac. According to wiki, it is not compatible with beta .75
Wiki for Spadille:http://aceofspadeswiki.com/index.php?title=Spadille
Website for Spadille:http://www.nateshoffner.com/projects/
The other browsers has no wiki/website.
If Spadille doesn't work, try the other browsers.
If none of them work...You have to look for another solution.
Disclaimer
I did not make Spadille or any of the browsers. This topic is to help players who have trouble connecting to the servers. Links were obtained from ace-spades.com.