Tell us what you have. Which firewalls, what OS version, what modem & router brand names & model no.'s, & where you're trying to connect from? Home, school, work, etc.? If yo can't open it it sounds suspicious. Did you totally Remove your previous LW version? Have you tried deleting your LW prefs found here: C:/Documents And Settings/your_username/.limewire (delete the folder called .limewire

Update your Java to the most recent: http://java.sun.com/j2se/1.5.0/download.jsp (take the JRE)

Try the latter 2 things if that makes no difference then post your other details here.