Every once in while when I publish a NuGet package and then try to use the published package in another project I end up with a situation where the new package simply is not recognized. Most of the time it shows up after a few minutes, but on more than a few occasions I've stuck waiting for quite a while waiting for the package cache to refresh. Luckily there's a way to nuke the cache and force Nuget to re-read local packages and while that is the nuclear option that requires downloading a lot of packages it works to make your project compile - right now!