elmah - an item with the same key is already exist

Question

I have one project in asp.net mvc in .Net Framework 4.5 and MVC 4.

I was installed elmah before some months ago and now I am trying to update the elmah but it is not showing me any update button so I removed all the elmah related things from my code but now when I try to install from nuget it gives me the error.

an item with the same key is already exist

Error page:

Answer 1

First of all show your package.config file if any packages have two times referenced or not than try to uninstall or install any new packages or existing packages.

Sometime after checking and changing in package.config file need restart of your visual studio so do it once and than check if it is working or not.