Error 0x8004505D

Value: -2147200931 | 0x8004505D | 2147766365

What does it mean ?

SPERR_NO_WORD_PRONUNCIATION  
The SR engine is unable to add this word to a grammar. The application may need to supply an explicit pronunciation for this word.
Value: 20573 | 0x505D | 0b0101000001011101

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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