Error 0x8051001E

Value: -2142175202 | 0x8051001E | 2152792094

What does it mean ?

OPC_E_DS_EXTERNAL_SIGNATURE  
A relationship whose target is a Signature part has the external target mode; Signature parts must be inside of the package.
Value: 30 | 0x001E | 0b0000000000011110

Where does it come from ?

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

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