Error 0x80040009

Value: -2147221495 | 0x80040009 | 2147745801

What does it mean ?

OLE_E_CANT_GETMONIKER  
Not able to get the moniker of the object
Value: 9 | 0x0009 | 0b0000000000001001
TAPI_E_CONFERENCEFULL  
The conference is full.
Value: 9 | 0x0009 | 0b0000000000001001

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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