NuGet app.config / web.config Transformation Trouble

This article details the author's experience troubleshooting NuGet package transformations for app.config and web.config files. The author encountered three interrelated issues: the test project was in TFS source control, package version was not incremented after adding transform files, and NuGet Package Restore was enabled. The latter prevented 'undo pending changes' from removing the installed package, causing subsequent installations to fail to apply updates. The solution involved manually deleting the package folder from the packages directory. This is a technical troubleshooting guide relevant to software development and DevOps.