Eventually, Windows will not allow installation of .exe apps.
For many Windows users, there will grinding of teeth, and suffering at the hands of change. Yet most users will be unaffected by this change, because they will no longer have any need for .exe apps, and not have any installed.
For security and other reasons, the “sandboxed” app model will fully replace all .exe apps. App developers will all port their .exe apps to store apps. Store apps are called “sandboxed” because they have restricted access to the OS and to other apps – and gain access in a controlled way by requesting “permissions”. However, .exe apps don’t have these restrictions and have the power to do a lot of damage.
Note that Microsoft has NOT officially stated that this will happen – but I am pointing out the steady progress toward this outcome.
The app package model is easier to manage, keep secure, control battery life and things that cost the user money. It has many other advantages over .exe apps.
It will be possible to install apps from outside of the store, but they must be application packages like store apps.
When most popular .exe apps have been ported to the store, Microsoft will likely start pushing the transition to ending .exe app installations. This may take a few years. There are many widely installed apps that are available only as .exe, and this even includes the Microsoft software used for making store apps.
There’s no need to panic. It will take a while to happen – and most people wont be inconvenienced.