Error 0x80EF01F8

Value: -2131820040 | 0x80EF01F8 | 2163147256

What does it mean ?

RTC_E_STATUS_SERVER_SERVER_TIMEOUT  
Server Time-out
Value: 504 | 0x01F8 | 0b0000000111111000

Where does it come from ?

FACILITY_SIP_STATUS_CODE  
SIP - Session Initiation Protocol (VoIP)
Value: 239 | 0x0EF | 0b11101111

Other Errors for FACILITY_SIP_STATUS_CODE