Error 0x80EF0258

Value: -2131819944 | 0x80EF0258 | 2163147352

What does it mean ?

RTC_E_STATUS_GLOBAL_BUSY_EVERYWHERE  
Busy Everywhere
Value: 600 | 0x0258 | 0b0000001001011000

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