Hiya...

With LW, primitive as it is, you are probably only experiencing a problem with whatever 'software' firewall you have installed.
(Note that it is the singular - firewall. If you have more than one 'software' firewall installed ((i.e. more than one internet security program)), then you are ALWAYS going to have problems).

Check your 'software firewall' app, if any... make sure that you have it running so that it auto-detects new apps, such as LW, when they try to access the net - BOTH in and out ! Or, use an 'interactive mode' if that is the way your app is written.

Now, it could, maybe, be an issue with a 'hardware' firewall if you have recently changed or reset a router...

Worst... The newer iterations of LW... for a VERY long time now as far as 'newer' could be defined, have had severe problems with firewall compatibility... It is the failure of the LW developers, not you.

There are 1,000s and 1,000s of posts on this topic, as you state you already know.

In order to clear your own butt, before firing your broadsides at LW...

Check to make sure that any router you MAY be using is not blocking a port or range of ports.... There is also, always, the sliiiiiim chance that your ISP has suddenly started blocking common p2p ports at the same time as your probem arising... Natch, this is near the perfect example of the 'Monte Carlo Fallacy' in statistics, but it's best to eliminate that also as a possible cause.

Saying all of the above, my bet is that it's just another apathetic screw-up from LW and I'd just use Phex or some other client and save all the pain, huh ?

btw... Because you did not mention the critical disaster words, "I recently upgraded/reinstalled Limewire...", I have not touched on anything about said disastrous act... !