Sina_Ter Said:
"HELP! Pages does not work anymore: Hello! I am in a bit of trouble after the last update in November 2020 - Big Sur 11.0.1 (20B29). After then, I cannot longer open any file previously saved with pages extension. Why is that? How can I fix it? Can I recover my previous files? Thanks all"
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Three Thoughts:
A. What is the extension?
Please provide the extension. It may pertain to an application needs to be re-downloaded..
B. Try Opening It "With" Something:
See what the default item is that this opens with. Then, see if you can open that Application.
- Right Click: on the icon.
- Hover Over: Open With...
- See what the default item is.
C. If Nothing Opens, Reinstall the macOS:
If that application cannot be opened, then you may need to reinstall the macOS.
1. First, Back up your Mac:
Create a Time Machine backup of your Mac, so that you can have something to restore your Mac from, should anything go wrong with the transfer.
2. Then, Reinstall the macOS:
Nothing would be deleted. It's just that items that have become corrupted or deleted, would be replaced or reinstalled back to where they should be. Go Here: How to reinstall macOS from macOS Recovery - Apple Support