To update or reinstall an executable stored in NuGet, you can use the NuGet Package Manager within Visual Studio. First, open the NuGet Package Manager from the Tools menu. Then, search for the package containing the executable you want to update or reinstall. Once you find the package, select it and choose the option to update or reinstall it. The NuGet Package Manager will automatically download and install the latest version of the package, including any new or updated executables.