Greetings!
I have had LW for about 3 yrs. now and this is a first for me. My system is detecting my firewall and it shows on the globe at bottom of the screen as being engaged. NOTHING has changed on my computer, this just started two days ago! What's up?

Have you been through your software firewall & double checked everything?
How do you have your router set up (are you using UPnP or port forwarding)?
Check the listening port, make sure it's still the same as it's always been. Mine's a bit demented & the port number changes sometimes, which throws out the firewall settings & port forwarding

This happened to me too. Nothing seems to work i even tried to force ISP and it didn't help either. This happened to a lot of people at the same time it seems hm....

Have you been through & double checked your firewall settings?
Firewall setup

Are you port forwarding? If so, try going through all the port forward setup once again. What version of LW are you using, must be pretty old if it has 'force IP'

Go through all the info here, see if anything helps
Connection problems? Check here first!

i've got the newest versio 4.12.3 or something.
If the port changes, do i have to change the settings as well?

Your listening port number has to be the same as the port number that you've allowed through your software firewall. If you're port forwarding, the port number that you've forwarded has to be this same number too.

i still get a message that says i don't have an active internet or a firewall is blocking LW from connecting. I only have windows firewall and it has it on its exeptions list and in the advanced section. ports are all the same. It just started doing this when I logged in about a week ago.

What's your connection like - do you have any green bars at all?
Do this test & see if it works
http://www3.limewire.com:6346

What are your details (sorry for any repeat questions!)

OS(Win XP etc)
LW & Java version (help > about LW & you'll see)
Firewall you're using
Modem/router brand & model
ISP
Connection type (DSL etc)
Where you connect from (home, school etc)
Are you sharing a connection with other computers
Is this your first try with LW

Have you tried using any other p2p apps & if so, do you have the same problems?

Windows XP
LW 4.12.3
Java
Linksys router (ethernet cable connected)
WOW internet and Cable
Connect from home
not sure what my ISP is
Router hooks up to 2 computers (mine and my family's)
Used LW for about a month
never tried P2P (not sure what that is)

P2p is peer-to-peer, file sharing apps like LW, BearShare, Morpheus etc etc

Did the port test work?
Do you have any green connection bars at all?
Your ISP = internet service provider. Who do you pay for your internet service?
What's the model of your LInksys?