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c#owinkatana

OWIN Webapi app receiving "System.ArgumentException no conversion available..." when bundled with nuget


I'm attempting to setup a self-hosted OWin app (using VS2012) - I think it's close since I can run OwinHost.exe from the directory containing the .csproj and application serves from localhost:5000 correctly. I created a default nuspec file and added the following

<files>
  <file src="bin\*.dll" target="bin" />
  <file src="views\home\home.html" target="content" />
  <file src="web.config" target="content" />
</files>

in AssemblyInfo.cs

[assembly: OwinStartup(typeof(TestA.Startup))]

When I install the package ( nuget install mypackage ) I get the following error...

Starting with the default port: 5000...

Error:  System.ArgumentException
No conversion available between 
System.Func`2[System.Collections.Generic.IDictionary`2[System.String,System.Object],
System.Threading.Tasks.Task] and Microsoft.Owin.OwinMiddleware. 
Parameter name: signature

Let me know if you would like more info

Cheers!


Solution

  • Go into Manage Nuget Packages for Solution... on the solution, choose Updates and click Update All (or select the owin related ones as applicable).

    This fixed it for me.

    Original Error:

    Error: System.ArgumentException No conversion available between System.Func2[System.Collections.Generic.IDict ionary2[System.String,System.Object],System.Threading.Tasks.Task] and Microsoft .Owin.OwinMiddleware. Parameter name: signature

    After Updating Nuget Packages:

    Starting with the default port: 5000 (http://localhost:5000/) Started successfully Press Enter to exit