I am working on an Asp.Net MVC 4 Application in which I am using SignalR 2.0.1 and I Mapped it using Owin Startup class and it worked fine at first.
All of a sudden when I tried to rebuild my app it said that the type are namespace IAppbuilder
could not be found.
Following is my start up class
using Microsoft.Owin;
using Owin;
using WhiteBoardApp;
namespace WhiteBoardApp
{
public class Startup
{
public void Configuration(IAppBuilder app)
{
app.MapSignalR();
}
}
}
I have installed Owin
package too, and for some reasons I could not find Owin Startup class so I just added a normal class and included all the references that are needed.
May I know where I am making a mistake
Try to use Package Manage Console and do
Update-Package Owin -Reinstall
I was having similar issue. But instead Owin, problem was causing Microsoft.Owin, obviously
Update-Package Owin -Reinstall
Didn't work, neither did Update-Package Owin
BUT
Install-Package Microsoft.Owin
did work fine for me, thanks.
The IAppBuilder interface is found under Owin package. Just add a reference in your class file:
using Owin;
And rebuild. Your project will pick this up.
I have no idea why VS didn't pick this up, but it didn't. Once I added this reference to my project, then everything fell into place.
I encountered the same problem while building my project. Here are the steps that helped fix my problem:
Solution Explorer
and look for your projectReferences
; You should see warnings on the problematic referenceReferences
and open Manage NuGet Packages
Microsoft.Owin
; After loading it shows that it is already installed (It is, but it installed incorrectly. Checking the properties > version at step 2 shows 0.0.0.0
)Force uninstall, even if there are dependencies on it
Cannot install
Microsoft.Web.Infrastructure
because it already exists in the packages folder. Rolling back...
Microsoft.Web.Infrastructure
Here are the alternatives I've read about to fix this kind of problem.
Good luck.
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