Error 0x8004010B

Value: -2147221237 | 0x8004010B | 2147746059

What does it mean ?

_MAPI_E_BUSY  
MAPI: The server is busy
Value: 267 | 0x010B | 0b0000000100001011

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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