All of My Decks are Gone/Restoration Is Blocked

[sl0771]

I am trying to open Anki as I do every day as a medical student, and I cannot access any of my cards/they seem to have been wiped from my account.

When I open Anki, I receive this message:

Then, when I try to open my username, I receive this message:

Then, when I try to restore a backup, I receive this message:

How can I adequately restore an old backup? I have tried restarting my computer and closing the application as the instructions suggest, but this does not work and I end up with the same messages again. I also tried making a second user account and restoring a backup there, but that also failed. Additionally, I can’t access the preferences within the Application when I try to fix the restoration settings. Lastly, I am using a Mac running Big Sur Version 11.2.3.

[abdo]

The first error message is caused by the Advanced Browser add-on. You may have to disable it.
See When problems occur - Frequently Asked Questions

Regarding the second error, this could be relevant:

Unable to open Anki

you have installed an older version of anki while your collection is for a newer version. install the previous version of anki that you had from here (you can install the latest beta/alpha version if you don’t know which version you had installed from here ) when you installed the latest version, go to “File -> Switch profile” and press “Downgrade and quit” then install the version that you want to use. it should solve the problem

[sl0771]

Thank you very much! I installed the latest version of Anki and my full collection was restored! Moral of the story: keep your apps up to date!