"appointments-es_ES.mo" file spanish causes "pages" wordpress dashasboard errorh

Hi,
I've just uploaded "appointments-es_ES.mo" file to the languages plugin directory. That's when the pages section on my wordpress stops working and doesn't load (screenshot). I'm sure the issue is caused by this file, cause i've discarted others. I've changed wordpress theme, disabled other puglis, reinstalled appointments plugin, and whithout this file it works perfectly.

I'sure i must be doing some stupid mistake, but i can't find an answer.

Thanks,
Eva