Won't sync events from Google: "Backend factory for source (...) and extension 'Calendar' cannot be found"

[o-alquimista]

What Happened?

Calendar fails to synchronize events.

This is similar to #734

Steps to Reproduce

1. Go to Online Accounts, add new IMAP account. Mine is a Google account.
2. Open Calendar. See error message in a red banner.

Expected Behavior

Mail app works (shows my email), but Calendar doesn't show any events.

EDIT: If I add the account from Evolution (OAuth2), the calendar works as expected.

OS Version

8.x (Circe)

Session Type

Secure Session (Wayland)

Software Version

Latest release (I have run all updates)

Log Output

No response

Hardware Info

Dell Inspiron 15 3583 (amd64 laptop)

[teamcons]

what messages show up when you open the calendar from terminal ? (command "io.elementary.calendar")

[o-alquimista]

what messages show up when you open the calendar from terminal ? (command "io.elementary.calendar")

No output on the terminal. Nothing.

[ernstki]

For what it's worth, sudo apt installing the evolution package (currently at 3.44.4-0ubuntu2 on 7.1/Horus) and running Evolution once appeared to fix this problem for me. After that, I just uninstalled Evolution (sudo apt remove evolution && sudo apt autoremove).

I am using a service provider other than Google, though, so it's hard to say for sure whether this will fix it for others. But I predict that the underlying issue is with evolution-data-server (at least on Horus) and thus not really Calendar's fault.

Evolution also threw up other, different error banners for this particular account, but didn't warn again after the first launch, so maybe it fixed whatever internal data structures were out of whack.

[o-alquimista]

For what it's worth, sudo apt installing the evolution package (currently at 3.44.4-0ubuntu2 on 7.1/Horus) and running Evolution once appeared to fix this problem for me. After that, I just uninstalled Evolution (sudo apt remove evolution && sudo apt autoremove).

I tried your suggestion, and the error message is gone! Sadly, my events are not loading — the calendar is still empty. Will try again after a reboot... you never know.

---

EDIT: After a reboot, my Google calendar completely disappeared from the Calendar app; more specifically, from the "Manage Calendars" button with a cog icon. Honestly, I give up. Will try again on elementary 9.

[AndreaMaietta]

i as well can not get google calendars to sync no matter what method above or otherwise have tried. The calendar app although beautiful is worthless at this point

[lobre]

Hey, I struggled a lot (and so I cannot tell the exact steps) but I ended up having it working for both Gmail and Google Calendar with the Evolution method.

I added and deleted my accounts many times, restarted my computer a few times, deleted my Evolution config directory multiple times, and at some point, it ended up working great. I did not touch anything since that day (it was a few weeks ago).

This is not a adequate solution, but as long as there is not a clean way to do it from Online Accounts (which seems complex if I understand well), it is still technically possible.

Hope that helps.

[AndreaMaietta]

Well I tried adding evolution and it only added everything there it didn't populate the calendar app or anything else. Am I missing something?

[AndreaMaietta]

https://youtu.be/6iADtIw5Lyw?si=n_xR-Q5Ow1l93doK

this is the solution works flawlesly!

[ernstki]

this is the solution works flawlesly!

Nice, thanks for sharing what worked for you! That gnome-online-accounts-gtk package is already in elementary OS's default package sources, though, so you might be able to skip all those steps about downloading it manually from Mint's web site.

Even though I myself don't always follow the prevailing advice either, it's good to at least be aware of the Debian project's cautions about mixing packages from different releases, as the theory applies equally well to Ubuntu/Mint/elementary OS.

It looks like the person who made the video is using elementary OS 8. This gives some credence to the idea that it's some combination of system libraries, rather than Calendar itself, which is still version 7 for everyone, no matter which elementary release they're on.