Error 0x8004004F

Value: -2147221425 | 0x8004004F | 2147745871

What does it mean ?

TAPI_E_PEER_NOT_SET  
The peer for this bridge terminal must be set to complete this operation.
Value: 79 | 0x004F | 0b0000000001001111

Where does it come from ?

FACILITY_ITF  
COM/OLE Interface management. FACILITY_ITF is designated for user-defined error codes returned from interface methods
Value: 4 | 0x004 | 0b00000100

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