Ok, if you uninstalled, can you try to connect with HyperTerminal again, and tell me the error you get. If you still get the COM port in use, then we will use PortMon to find out what process is screwing up your system. Make sure Elk RP isn't running either.
Update; I get that COM port in use error now as well, odd, I used this software just a few days ago while I never shut down HS. Either way, try the hyper terminal suggestion now that you uninstalled HS.