The Fusion logs report a warning saying :
WRN: Multiple versions of the same assembly were loaded into one context of an application domain: WRN: Context: Default | Domain ID: 1 | Assembly Name: Microsoft.Office.Interop.Access, Version=15.0.0.0, Culture=neutral, PublicKeyToken=71e9bce111e9429c WRN: Context: Default | Domain ID: 1 | Assembly Name: Microsoft.Office.Interop.Access, Version=16.0.0.0, Culture=neutral, PublicKeyToken=71e9bce111e9429c WRN: This might lead to runtime failures. WRN: It is recommended that you remove the dependency on multiple versions, and change the app.config file to point to the required version of the assembly only.*
Where as, i haven't referred the version 15.0.0.0 DLL anywhere. It automatically gets picked from the GAC. the log file further says:
LOG: Using machine configuration file from C:\Windows\Microsoft.NET\Framework64\v4.0.30319\config\machine.config. LOG: Post-policy reference: Microsoft.Office.Interop.Access, Version=15.0.0.0, Culture=neutral, PublicKeyToken=71e9bce111e9429c LOG: Found assembly by looking in the GAC. LOG: Binding succeeds. Returns assembly from C:\WINDOWS\assembly\GAC_MSIL\Microsoft.Office.Interop.Access\15.0.0.0__71e9bce111e9429c\Microsoft.Office.Interop.Access.dll. LOG: Assembly is loaded in default load context.