Error 0x80043621

Value: -2147207647 | 0x80043621 | 2147759649

What does it mean ?

FTE_E_EXCEEDED_MAX_PLUGINS  
The maximum number of plug-ins has been exceeded, so a new plug-in can't be loaded.
Value: 13857 | 0x3621 | 0b0011011000100001

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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