No 'Access-Control-Allow-Origin' header is present on the requested resource
Most of us will saw this error message in web browser console while working with ASP.NET WEB API. The reason behind this error is CORS. That means Cross Origin Resource Sharing. When we try to access a web service from our application, if the application domain and the web service domain is different, then this problem will be occurs. For example: Suppose our application is running on www.examplesite.com from where we are trying to access the web service which domain address is www.exampleservice.com/api/employee . Since the domain address is different, it through the error. What we can do? In our Web API Application: 1. Go to Tools 2. Nuget Package Manager 3. Package Manager Console 4. Write install-package Microsoft.AspNet.WebApi.Cors 5. Now go to WebApiConfig.cs file 6. Paste the following lines: EnableCorsAttribute cors = new EnableCorsAttribute ( "*" , "*" , "*" ); config.EnableCors(cors); and you are DONE!