I have a fresh install of Visual Studio 2015 community with Windows 10 UWP SDK running in my computer. Recently I tried to open a project that I imported from another computer a
I had this problem about a week ago, and ended up installing VS again from the Microsoft site. The download that fixed my problem was "Visual Studio Community - with Update 1" from here.
Had a few issues with code compatibility afterwards and had to reinstall a few SDKs, but other than that it fixed the "update required" prompts.