danmyman and Canadian:
Are you both saying that, if you have turned off the Redirector service once and started LimeWire, then on subsequest occasions where you use LimeWire the original problem does not come back? (i.e. LimeWire still works after rebooting the PC or turning on the Redirector service).

What does the redirector service do? What are the possible consequences if I leave it off?

Leaving the Redirector service off is not a good idea as it, in effect, disables parts of your McAfee security package.