Error 0x80EE0017

Value: -2131886057 | 0x80EE0017 | 2163081239

What does it mean ?

RTC_E_SIP_TRANSPORT_NOT_SUPPORTED  
The Transport specified is not supported
Value: 23 | 0x0017 | 0b0000000000010111

Where does it come from ?

FACILITY_RTC_INTERFACE  
RTC - Real-time Communications
Value: 238 | 0x0EE | 0b11101110

Other Errors for FACILITY_RTC_INTERFACE