Run it often
The Windows App Certification Kit test is one of the first things that happens to your application during certification – and if you fail it, your submission fails. The good news is that the WACK is also something you can run locally before you submit. Please do. In fact, why not integrate it into your build process or get into the habit of running it whenever you are making significant changes to the code.
Also run it on a low spec machine
However as well as running it frequently, also run it on a low spec computer (or Virtual Machine) – Atom is a good processor to aim for.
And run it on clean machine where your application has never run
Just in case you are seeing a performance boost from “caching of something”…
Creating a package gives you the option to launch the kit:
or just type “windows app cert” into the search charm:
And there is a command line to use as well:
appcert.exe test -apptype metrostyle -packagefullname [package full name] -reportoutputpath [report file name]