I got the following error: \"An error occurred during the parsing of a resource required to service this request. Please review the following specific parse error details a
In our case - deleting all the contents of a published intranet site, and republishing the project that worked fine in debug fixed the problem.
I had this exact same issue when I downloaded the project source into two locations. The issue turned out to be by downloading the source it altered the sites virtual directory location and since I had not rebuilt the second source there were no DLLs there.
Fixed
In my case, it helps: if you use a folder other than the default project ( naprmer on the D drive , in the case of Windows), then change to the default folder , create the project , run it. Then again, you can create projects in the folder in which you want . Strange. But this has helped in my case.
This happened to me when i was trying to merge two solutions. the problem was the namespace was not well configured in all files. one part of story solved with @Kevin Aenmey answer but many other's ... not!
so the only way for me was to search for old namespace in the whole solution and replace them all with new namespace.maybe not the best option but in case of bad luck works nice
In my case the solution was the next:
Then, verify the Global.asax.cs and I found this:
public class Global_asax : System.Web.HttpApplication
Therefore, I changed the attribute Inherits in my Global.asax, and finally the markup was the next:
Inherits="NameOfMyProject.Global_asax"
Also, I started the: ASP.NET state service, in the Administrative Tools. Then, my app run normally.