Win 10 Pro Changing Default Apps Back To It's Ms Ones

I use Cyberfox as my browser and Irfanview for pic viewing....... I set them, and if I restart the PC, Win 10 changes them back to their Microsoft defaults.... leaving messages in the "Action Center" that "an app caused a problem with the default app, therefore changing back, to the Edge Browser and the Win 10 viewing prog.... Any ideas as to what is happening?? Thanks ahead of time !!!

 

It might depend upon which 'ring' you are in, and/or whether Windows is authenticated or not as to how heavy handed MS are with overriding your settings, if this is just a normal upgrade install or a PC bought with W10 ready installed, then you should be able to keep your choice of software providing they're all stable and fully compatible with W7.

You can opt to disable Edge from within the Windows components settings, likewise you should be able to control the individual programs/file types under normal circumstances.

 

This is an authenticated upgrade from Win 7 Pro, to Win 10 Pro. I'll look up the Edge options as you have suggested and such and see what happens... Thanks for the reply.... !