When port forwarding, did you choose to make the exception for both TCP & UDP? It is actually more effective to do a separate port forwarding for each.

Also, in your computer's firewall, both TCP & UDP exceptions for the port ranges should be created (may need to create sub-rules to do this.) Setting up an exception for LimeWire in your software firewall (click in link)

You may wish to check this If LW 5 Will Not Connect as sometimes things like Advanced settings -> Performance might affect things.

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