iCloud Calendars Aren't Syncing from Mac to iOS - The server responded with "500" to operation CalDAV...

thomasdangit

macrumors member
Original poster
Sep 16, 2014
30
9
Dallas, TX
Hi everyone!

Recently (as of 2 days ago), I noticed that my iCloud calendar on my Mac is taking forever (and sometimes never) to sync to my iPhone. I've tried going into Calendar > Accounts on my Mac and then toggling "Calendar" off, quitting the app, re-opening the app, and then toggling "Calendar" back on. I get a symbol at the top left of my Mac Calendar app: an exclamation mark inside a triangle.

Screen Shot 2020-02-03 at 12.54.46 AM.png


The the error message I get when I click on the symbol is attached. It says:

Your calendar request couldn't be refreshed.
The request for account "iCloud" failed.
The server responded with "500" to operation CalDAVAccountRefreshQueuableOperation.

Screen Shot 2020-02-03 at 12.54.23 AM.png


I'm running Mac OS Catalina (latest version, but on beta—does this matter???) and then the latest version of iOS 13 on my iPhone. Curiously, when I create new events on my iPhone, it appears almost instantly on Mac, but not the other way around.

Does anyone have any ideas or anything to help? My calendars are my daily drivers, and I would really appreciate it!
 

Attachments

thomasdangit

macrumors member
Original poster
Sep 16, 2014
30
9
Dallas, TX
Exactly same problem here!
Hmm...Solidarity always feels better.

Anyways, what software versions are you running?

My iPhone is running iOS 13.3.1 and my Mac is running macOS Catalina 10.15.3. I was on the developer beta as of yesterday, but then deleted the β profile, re-downloaded regular Catalina from the Mac App Store, and installed it.

Still having the issue.

I've reached out to Apple and they chalked the problem up to the Mac being on β software. It is no longer.
 

mnc042

macrumors newbie
Nov 16, 2008
12
2
New England, USA
Same here! I've been searching this error and coming up with a ton of hits, none of which matched my situation, but this started happening over the weekend and it hit both of my MacOS machines (I have two logged in to my iCloud account) at the same time. They aren't getting updates, and any appointments entered on the Mac do not push to the cloud.

My calendar is fine between my iOS devices, though -- if I didn't have any MacOS machines, I wouldn't notice any problem at all.

I'm glad I'm not alone.. but.. now what? :)

Edit: macOS version 10.15.3 on both machines. iOS 13.3.1 on all iDevices.

\marc
 
Last edited:
  • Like
Reactions: thomasdangit

mnc042

macrumors newbie
Nov 16, 2008
12
2
New England, USA
So I just got off the phone with Apple, as well, and they are running it by engineering (after running through the Tier 1 / Tier 2 support scripts).

Interestingly, booting up in Safe Mode makes the issue go away for a few minutes, during which time events sync normally back and forth, but then ultimately the error reappears and the calendar goes back to not syncing.

It's baffling, and very sudden, after running for a good long time without any issues at all.

\marc
 
  • Like
Reactions: thomasdangit

thomasdangit

macrumors member
Original poster
Sep 16, 2014
30
9
Dallas, TX
So I just got off the phone with Apple, as well, and they are running it by engineering (after running through the Tier 1 / Tier 2 support scripts).

Interestingly, booting up in Safe Mode makes the issue go away for a few minutes, during which time events sync normally back and forth, but then ultimately the error reappears and the calendar goes back to not syncing.

It's baffling, and very sudden, after running for a good long time without any issues at all.

\marc
Thank you for calling Apple! Hilarious they ran it by engineering...I've never heard of them doing that. I gave Apple a call but it seems like they'd only give me the Tier 1/Tier 2 support scripts, and part of that script involved getting off the beta macOS version and spending 1 hour downloading the regular version from the Mac App Store. I hung up before it finished. I installed the non-beta Mac OS Catalina version but the syncing still didn't work.

Interesting about Safe Mode. I've never used that, but as you said, didn't seem like that would solve the issue.

I just re-checked my calendars (it's Tuesday 2/4/2020 at 11 PM CST) and the calendars are syncing again like magic! The exclamation mark has disappeared and events are syncing like normal and very, very quickly! Seems like your call to Apple engineering worked after all. :)

How's it looking for you?
 

adrianlondon

macrumors 68000
Nov 28, 2013
1,834
1,575
Switzerland
This sounds like a glitch with iCloud itself, if it started (and stopped!) all of a sudden. Of course, I don't know for sure and am just basing it on what a 500 error means when trying to load a webpage. Annoying that Apple Support don't have better access than us to some kind of services status page.
 

BrianBaughn

macrumors 604
Feb 13, 2011
6,526
1,020
Baltimore, Maryland
It's just wonky…iCloud calendars. A couple of weeks ago I was trying to share an iCloud calendar to someone with an iPad on iOS 12. It just wouldn't work even after all the usual troubleshooting. Updated the iPad to iOS 13 and it started working.
 

mnc042

macrumors newbie
Nov 16, 2008
12
2
New England, USA
Well, here's the thing. Something seems to be a little better tonight. My calendar was reporting the error most of the day, but I just rebooted and fired up the calendar and the error is gone, and my calendar seems to be syncing again. I tried adding a new event on the phone, and it appeared very quickly on the desktop.

Then, about five minutes ago, the error re-appeared and I'm back to square one. No good.

I've also noticed that even during the (relatively small) window where it worked, the exclamation point would appear very quickly, then go away. Now, it's just back.

I think something is wrong on the iCloud side. My feeling is that it's a single server out of the many they have handling the load balancing, and it's just random luck if that one happens to be handling your requests. The 500 error is a server-side error (Internal Server Error) being thrown from the WebDAV server that underlies the iCloud service. Now, it's possible that the client is sending something to cause that error, but it's strange that it happens, goes away, happens, goes away...

Oh, hey -- as I'm typing this, the error disappeared again. Wonder how long it will stay away this time?

I'm convinced it's something on the iCloud side. I just can't figure out why it's only affecting a few of us.

\marc

EDIT 1: Oh also, Apple says they're holding my case open until engineering gets back to them. They said it can be up to 48 hours, so by tomorrow evening. We'll see!

EDIT 2: And now the error is back. Peachy.