[Timucin]

Previously I was able to view the books I had with the kfx extension with Calibre, but now it gives me a warning like this:

calibre, version 6.23.0
ERROR: No associated program: Windows will try to open byn alqSryn - njyb mHfwZ.kfx with calibre itself resulting in a duplicate in your calibre library. You should install some program capable of viewing this file format and tell Windows to use that program to open files of this type.

But before I could open these files, what changed? Did the Calibre update cause this?

How can I solve this?

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At the same time, when I want to convert these KFX books, it gives me this warning: calibre, version 6.23.0
WARNING: Could not convert some books: Could not convert the book because no supported source format was found

ثلاثية القاهرة: بين القصرين، قصر الشوق، السكرية - No supported formats (Available formats: kfx)


I could easily convert them to PDF before.