I'll add my 2c, since the tutorial doesn't address the reasons why this notification:
- Has been introduced in Windows 8
- Doesn't always show after you install a new program
I've covered the first point in a different post, so I'll copy-paste to keep all relevant info in one place.
The file type associations model has changed in Windows 8. In short, if a file type is already associated with a program, you can't change it from within another program. Everything must be handled through system dialogs, such as
- Default Programs in the Control Panel
- Open With dialog
- a new notification "You have new apps..."
The idea is to put the user in control and prevent other programs from changing file associations without user approval.
IrfanView is an example of incompatibility with Windows 8. You can set checkboxes during or after install, but they won't affect file types already associated with other software. It can only take over file types that have not been associated. The dialog shown below is deceptive.
Firefox is an example of compatibility with Windows 8. If you have, say, IE as default and try to set Firefox as default from its settings, you'll see a system dialog. In other words, Firefox calls a system dialog, so you can set the default browser, which is basically HTTP/HTTPS protocol handling and HTML/HTM file association.
If you want to associate file types with another program, you've got three main options:
- In "Set your default program" make it default for all types its registered for or choose defaults
- In "Associate a file type or protocol with a program" choose a program for a specific file type
- Right-click a file - Open With - choose a program
There's another option in a form of a new program notification that you see first when you install a compatible program. But if you skipped it, these three options work. And they work pretty much the same way as in Windows 7
The explanation for the second point is that an application must register in the system correctly. If it does not, it's not fully compatible with Windows 8, and you won't see the notification. Going back to the IrfanView example, it does register for its file types.
For example, ff you changed file associations from IrfanView settings, they wouldn't apply, but when you try to open such file type, you'll get a new app notification.
As a side note, these notifications aren't perfect, because they are displayed for a short period of time, and it's easy to skip them. However, they are an important part of the UX, because they simplify file and protocol association for the end user.
While I understand that some people find them annoying, completely disabling them makes you jump through additional hoops in order to associate a file type or protocol with a new program. The hoops aren't that bad, because the dialog shown below still pops up when you try to open file that can be opened with a new app.
For more technical info, see File type and protocol associations model (Windows)