Probably b/c you haven't configured your firewall to allow LW full access.

Do this test: Bug Report instructions & sample image Is it True/False? If false then you're firewalled which means it'll be very difficult for people to upld from you. If you upld it improves LW's perfomance for searches & downld results.

Configure your firewall here: http://www.limewire.com/english/content/firewalls.shtml