Error 0x80042601

Value: -2147211775 | 0x80042601 | 2147755521

What does it mean ?

NOTESPH_E_UNEXPECTED_STATE  
An unexpected error occurred in the Notes protocol handler while processing the URL.
Value: 9729 | 0x2601 | 0b0010011000000001

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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