Question: How do you solve Asp.Net 5 Error: "InvalidOperationException: Unable to resolve service for type 'System.IFormatProvider' while attempting to activate 'RepositoryService'." Answer: If you want to resolve this issue do not try to inject IFormatProvider through the Constructor as this Interface comes with Asp.Net 5 Implementation. There is no need to request the IFormatProvider from the Dependency Container. However, just define the property as below: private IFormatProvider _provider; function myFunc(){ int myInt = Convert.ToInt32(YouString,_provider); } As a rule of thumb, always test your code before you deploy to production, understand how you would test different scenerial regarding Globalization and Localization. See Related Article here.