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Each time I open Calendar on my MacBook Pro (MacOs 10.15.7 Catalina) there's a warning triangle under my Yahoo account. When I click on the triangle it brings up the box in the attached screenshot. What can I do to correct this please?
[Edited by Moderator]
MacBook Pro 13″
Hello John the Greek,
Thanks so much for posting in Apple Support Communities.
Looking in the Calendar User Guide there is an option for refreshing your calendars. There are several steps you can try. Here is the link directly to that page: Refresh calendars on Mac - Apple Support. This article also includes the following that we wanted to point out:
If you see a warning symbolnext to a calendar you published, shared, or subscribed to, Calendar is unable to connect to the calendar account. Check your internet connection and try refreshing or updating the calendar again.
Also, make sure the calendar hasn’t been deleted or moved. To see the calendar’s web address, Control-click the calendar’s name, then choose Get Info.
Here is a link for the Calendar User Guide for Mac - Apple Support, just be sure when searching for an article that you select the correct version for your Mac, macOS Catalina 10.15 is an option available.
Reach back out if you still need help.
Take care!
Hello John the Greek,
Thanks so much for posting in Apple Support Communities.
Looking in the Calendar User Guide there is an option for refreshing your calendars. There are several steps you can try. Here is the link directly to that page: Refresh calendars on Mac - Apple Support. This article also includes the following that we wanted to point out:
If you see a warning symbol
Also, make sure the calendar hasn’t been deleted or moved. To see the calendar’s web address, Control-click the calendar’s name, then choose Get Info.
Here is a link for the Calendar User Guide for Mac - Apple Support, just be sure when searching for an article that you select the correct version for your Mac, macOS Catalina 10.15 is an option available.
Reach back out if you still need help.
Take care!
Hello John the Greek,
Does that prompt still persist after booting your Mac into safe mode using the steps below?
1. Turn on or restart your Mac, then immediately press and hold the Shift key as your Mac starts up.
2. Release the key when you see the login window, then log in to your Mac.
3. You might be asked to log in again. On either the first or second login window, you should see ”Safe Boot” in the upper-right corner of the window. If you can't start up in safe mode, make sure that your Mac isn't using a firmware password.
You can also find those steps in this resource: Use safe mode on your Mac - Apple Support
It can take a few extra minutes to boot into safe mode. Your screen may flash or flicker while in safe mode. Those behaviors are expected. Testing in safe mode runs a check on your disk, removes some cached files, and can help isolate conflicts with startup items. Once you've tested that behavior in safe mode, you can restart to leave safe mode.
Should that still continue, do you have another other calendar accounts set up on your Mac? If so, are they exhibiting the same behavior?
Also, do you have your Yahoo calendar set up on any other devices?
Let us know, and we'll keep moving forward from there.
Hey John the Greek,
Are there any other 3rd party accounts syncing with the Calendar app on your Mac? If so, do they sync as expected or have a similar error?
If you haven't already, try deleting, then adding the account back in Calendar on your Mac. This will ensure that you have a fresh connection to the Yahoo server: Add or delete calendars on Mac - Apple Support
If you still the the error, reach out to Apple Support directly for a closer look: Get Support
Take care.
I'm replying to my own post because I don't seem to be able to edit it any more. I've now edited the graphic that I uploaded to get rid of the personal info that the admins here edited by removing the graphic altogether, which was fine, I understood the reason, but I wanted people to see the rest of the message...
OK, I started up in Safe Boot mode, then rebooted again. The problem's still there. I'm running my calendar in sync with my iPad (9th Gen, IOS 16.6.1) and the iPad Calendar doesn't show any warnings at all. Plus I notice that all events on the calendar sync happily, so I don't quite get what it means by telling me only on the Mac that "The server responded with “400” to operation CalDAVAccountRefreshQueueableOperation."
Any more ideas? And BTW, thx for your time, I appreciate it.
Thx to all who tried to help, truly appreciated. It seems to have fixed itself. I don't quite know how or why, but the only person whose advice I actually had time to apply was you, chuckbl, so maybe that's what did it. Anyway, the calendar now shows all the accounts and there are no warning triangles any more. Yippee! I was just now going to see what I could to do follow bbesspete's suggestions when I opened the Calendar to see that all was OK. This forum is excellent!!
Calendar server error 400
