Okay, the problem is I go to several locations on campus and the wifi I usually use (apogee) works fine with VO, but when I go to a different location and secure wifi network where you login from a webpage on firefox, VO gives this error:

Connecting to update1.vendetta-online.com:21024...
Connection timeout!
Connecting to update2.vendetta-online.com:21024...
Connection timeout!
Can't reach any Guild Software update server!

-----------------------------------------------

Unable to connect to the Vendetta Online
update server. Please ensure that you are connected
to the Internet. You may need to configure any
personal firewalling software or check with your
network administrator.

For more information on using Vendetta Online with
firewalls, see
http://www.vendetta-online.com/firewalls.html

-----------------------------------------------

But despite this, all the webpages run fine like nothing happened! It can't be a problem with firewall because it worked on a different wifi network... any idea what is wrong?

Some of them wifi hotspots will only let you connect to port 80 or port 8080, meaning you cannot play games, download torrents/mules etc. Try see if you can play another online game using that hotspot to eliminate this issue.

Yes, I've played several different online games on this network before, has never been an issue