Error 0x8004500A

Value: -2147201014 | 0x8004500A | 2147766282

What does it mean ?

SPERR_FILEMUSTBEUNICODE  
The file must be Unicode.
Value: 20490 | 0x500A | 0b0101000000001010

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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