Error 0x80040042

Value: -2147221438 | 0x80040042 | 2147745858

What does it mean ?

TAPI_E_MAXTERMINALS  
The maximum number of terminals has been reached.
Value: 66 | 0x0042 | 0b0000000001000010

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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