Error 0x8004501B

Value: -2147200997 | 0x8004501B | 2147766299

What does it mean ?

SPERR_LEX_VERY_OUT_OF_SYNC  
The client is excessively out of sync with the lexicon. Mismatches may not be incrementally sync'd.
Value: 20507 | 0x501B | 0b0101000000011011

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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