Error 0x80040015

Value: -2147221483 | 0x80040015 | 2147745813

What does it mean ?

TAPI_E_INVALDIALPARAMS  
Invalid dialing parameters
Value: 21 | 0x0015 | 0b0000000000010101

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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