Windows 10: Very sudden change in system behavior and can't open certain files

Something very strange started happening with my computer today. Here's a list of symptoms:I started my laptop Windows 11 from sleep state, and there was a dialogue open from Norton on the screen. I don't remember exactly what it said, but the gist of it was it was asking to scan my newly inserted USB device, only the "USB device" showed as my internal 2TB HDD hard drive. I have a 500gb SSD and the 2TB HDD. Windows is installed on my SSD. I clicked cancel on the dialogue.I noticed immediately that all the programs I had previously pinned to my taskbar were no longer pinned. The default taskb

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How to change default app to open certain file types.

It's not as simple as it seems
Although it's easy as pie to change default apps by type file, but how to do it if I want to use app that's not on the default Window list?
Like in this example,



File is opened by IE but I have installed in my system programme called Notepad++ and I want it to open .xml files whenever i double click on them. But Notepad++ is not on the Windows list



So how to set this up to open .xml files with Notepad++?

 

opening .dds files with gimp

Simply, HOW? I got the DDS plugin but the POS wont open DDS files still. Can someone give me a step-by-step rundown of how to install the DDS plugin for gimp so I know if I'm missing something?

 

A change in System Image's behavior?

It looks like you can restore a system image to C: without losing files that are already there. Is this a change in System Image's behavior?