USB Com ports used by other programs

I am trying to program some XBEE S2C modules. everything was fine yesterday but now when i connect and try to use xctu i get the error that the com port is being used by another program. I have restarted my laptop, uninstalled old com ports, tried different boards (using the groove xbee dev ones) nothing works and i really need to get some testing done. right now it feels like i need to buy a new laptop as everything is broken. (its not an old laptop just cant get windows to behave)
please help!
Rob Berry

You could try reloading the USB drivers for the boards you are working with.