System.Data.MetadataException: Unable to load the specified metadata resource

Question

My connection strings are as follows:

Answer 1

If you are unsure of what the correct path is for your Metadata files, you can find out by compiling your application, then opening the DLL using JetBrains' dotPeek and looking in the Resources folder to find the .csdl etc. file.

Answer 2

I had the same problem and, in my case, the problem was on changing the Model and the file named "...Web Deploy.pubxml" had the "metadata=res:///Models.**.csdl", etc. with the incorrect name (not updated). After manual correction it worked!

Answer 3

I also encountered this problem and it was because I was going from Entity Framework Model First to Entity Framework Code First, and had forgotten to change the EDMX connectionstring to a 'regular' connection string.

Answer 4

This answer is specific for Devart Entity developer edml file.

When I upgraded the csproj format(Visual studio 2017 with simple format) I got this error. The csproj has a feature where you don't need to include each file instead it includes all the relevant files under the folder by default so the entity framework files are treated same way as cs files so those are not embedded into the assembly by default.

I need to manually change the build action of my edml file to 'DevartEntityDeploy' which resolved my problem.

Answer 5

I've had a similar product with devart mysqlconnect - maybe this might help.

I have a project called EFModels which contains the .edml file and is referenced by other projects.

I noticed that the Release version of a project that referenced EFModels contains the EFModels.dll but it was much smaller in size (127kb vs 437kb) than the Debug version of EfModels.dll. Moving the EFModels.dll from the debug version into the Release version solved the issue for me as for some reason the Release version did not embed the ssdl etc.

Answer 6

I used EntityFramework 6.0 in one solution which included multiple projects such as WebSite level project, DataAccess level project. In my solution, the migrations should be happened in DataAccess level project.

When I run Add-Migration command in Package Manager Console, raised "Unable to load the specified metadata resource".

Finally, I found I set the WebSite level project as "Startup" project and this trigger above exception. It seems system will auto checking the connection string settings in the StartUp project first. And my data connection string set in WebSite level project is

"metadata=res:///ApplicationEntities.csdl|res:///ApplicationEntities.ssdl|res://*/ApplicationEntities.msl;provider=System.Data.SqlClient;provider connection string="data source=.;initial catalog=YourDatabaseName;integrated security=True;MultipleActiveResultSets=True;App=EntityFramework""

which is not correct for code first.

The correct connection string should be:

"Data Source=.;Initial Catalog=YourDatabaseName;Integrated Security=True"

Conclusion, always check the "connectionStrings" section in web.config in the "StartUp" project of solution first.