Can't create App packages anymore
I don't know why but after upgrading Microsoft to the insider preview version. I know, it's always a bad idea to update anything but had to do it to get the new MR Headsets to work...
I downgraded again after visual studio was unable to create any app packages. And it still doesn't work.... tried to repair visual studio and still nothing. I know it's a VS issue because i can't even build older projects which always worked and which i haven't touched.