Error 0x80040006

Value: -2147221498 | 0x80040006 | 2147745798

What does it mean ?

OLE_E_NOCACHE  
There is no cache to operate on
Value: 6 | 0x0006 | 0b0000000000000110
TAPI_E_ALLOCATED  
The device is already in use.
Value: 6 | 0x0006 | 0b0000000000000110

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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