I'm german and hope you understand my english

I want to activate my bluetooth gps receiver with vistumbler but it shows "Cant open gps port"??
I'm using visualgps and netstumbler to test the bluetooth gps connection and all worked fine!
If I choose the other options in vistumbler from kernel to netcomm ocx or to commmg it didn't work to!
Oh last but not least my OS is Windows 7 Home Premium 64 bit
Could anyone help me please how to activate or to open this port??
thank you marcel