Dontcha just hate answers that don't answer anything? Why would someone post that stupid reply is completely beyond me but ya know how some people are>Here ya go?
RNAAPP (Remote Network Access Application) is a core executable for Microsoft Windows Dial-Up Networking. RNAAPP can create a problem when trying to get Internet access by sometimes sticking in memory from a previous session, or too early in a dialup attempt, thus making your system believe that a connection is already established. The error messages "Dial-up Networking could not-establish a compatible set of network protocols'", "No dial tone", "Unable to Open Communications Port", "The Line is Busy'", "The Modem is Being Used'", and "Error 602: The Port is Already Open" are all common errors that you may receive with RNAAPP improperly loaded into memory.
AND the site where I gleaned this info:
http://www.modemhelp.net/newsletter/dun/combatrnaa
pp.shtml