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EasyDaClient - WCF - The type initializer threw an exception

01 Apr 2020 17:17 #8342 by support
Please check your target directory whether it contains following assemblies:
- App_Web_OpcLabs.EasyOpcClassicRaw.amd64.dll
- App_Web_OpcLabs.EasyOpcClassicRaw.x86.dll

If not, copy them over from QuickOPC installation (under Assemblies\net47). Visual Studio sometimes forgets to copy them.

Best regards

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  • Math
  • Topic Author
  • Visitor
  • Visitor
01 Apr 2020 12:41 #8338 by Math

I dont have any issue using the EasyDaClient with a Winform.

When I use the EasyDaClient within a WCF service I get this error:

The type initializer for 'OpcLabs.EasyOpc.DataAccess.EasyDAClient' threw an exception.

Here's my code:

Imports System.ServiceModel
Imports System.ServiceModel.Activation
Imports System.ServiceModel.Web
Imports OpcLabs.EasyOpc.DataAccess

Public Class WCFQuickOPCAjax

Public Function Test() As String
Dim Client As New EasyDAClient

Return "test"
Catch ex As Exception
Return ex.Message.ToString
End Try

End Function
End Class

I someone could help me I would be happy as a clam in high water!

Many thanks,


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