I've got a Kindle Fire HDX 8.9, and some CBZ comics that I converted with Kindle Comic Converter to MOBI, and then transferred to the device using Calibre.
This workflow has worked fine, until this week. Now anytime I try to open up a comic, I only see a blank white page. I can tap on the screen and view the number of pages, which matches what it should be, but no actual comic pages.
I've tried restarting several times (including a hard reset), force stopping the Kindle application, clearing its cache, and resending the comics using Calibre. Nothing has worked. I did notice that some items I had deleted from the device had reappeared on the home screen carousel as new. I tried opening one to see what it was, and that's when the blank screen started. I know that Calibre still sees a book as on the device, even when I delete it from the device (not through Calibre). However, I've never had problem until now, and have not seen deleted items reappear.
I'm using Calibre Portable on Windows 7.
I also tried reconverting an original CBZ file, and it only displays properly when I copy it to the Documents folder manually, but not with Calibre.