How to Upgrade NAV

Today, Microsoft has published new article about best practices and tips and tricks in upgrading process when you want to upgrade your solution to NAV2013R2 or NAV2015. The main reason why to read this article is because, the Classic Client is no longer supported by Microsoft. Now, it is the right time to make upgrade of your old NAV version.

Anyway, you can find awesome article about this upgrade process here on MSDN Blog. I recommend this article.