Error 0x80040D9F

Value: -2147218017 | 0x80040D9F | 2147749279

What does it mean ?

GTHR_E_NOTIF_EXCESSIVE_THROUGHPUT  
Alerts failed because of network failures or because the internal cache size was exceeded. If the problem persists, change the content source type to adaptive or crawl.
Value: 3487 | 0x0D9F | 0b0000110110011111

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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