Error 0x80510009

Value: -2142175223 | 0x80510009 | 2152792073

What does it mean ?

OPC_E_NONCONFORMING_RELS_XML  
The relationship markup does not conform to the rules specified in the OPC.
Value: 9 | 0x0009 | 0b0000000000001001

Where does it come from ?

FACILITY_OPC  
Open Connectivity Service (Package Consumption)
Value: 81 | 0x051 | 0b01010001

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