I have a major problem with project configurations. Everything started when I wanted to add new solution configuration (named \"Dev_WithSource\") based on existing \"De
Double click your Solution > Configurations > General.
Click on your 'ConfigToRemove' in the list then Remove (Ensure you tick delete also Configurations in Solution items), then Yes.
Click OK to save your changes.
Now, right Click on Solution and Tools > Edit File.
Go to "GlobalSection(SolutionConfigurationPlatforms) = preSolution" and remove all the Configurations you no longer need otherwise they will still show up in Configuration Mappings even though there are no mappings in the project!