Unable to sync Calendar App after iOS 18 update

Any updates on this? Same issue on my iPhone 16 pro max. Have done everything possible with corporate IT, and I’ve reset the network settings on iPhone. Exchange calendar still does not sync with iPhone native Calendar or third party apps. Agree that is difficult to keep 2 calendars without double booking or missing meetings. Frustrating since this is a new problem that I haven’t had in the 8-10 years using the same setup.

This is clearly a widespread issue, reading comments on multiple sites (here, Reddit, Microsoft).

We are having the same issue on my husband’s phone! He tried creating a new calendar and moving everything to that calendar and it had the same issue! But it isn’t affecting any other family member’s calendar. This is BEYOND frustrating because we are missing business meetings!!!

Same here, since updating to IOS18, all of my calender entries have disappeared and when I try to restore them from my Icloud there are no calender events there either. Everything else is backed up, my notes, my photos, it's all there, just the calender is empty - it says no archives available. I am freaking out, it had ALL of my appointments and I have no idea what to do now. Help please

Me, too, and I am so so so very very unhappy ever since doing a Software Update to my iPhone 13 which is not even a year old. I never called Apple to ask for support to do an Update.

This Customer Support person Lisa instructed me to do this Software Update without warning me what would happen after the Software Update which I soon learned the Software Update was the IOS 18.0.1 and now I LOST ALL my contacts and my past present and future calendar appointments.

Now, they tell me they cannot help me to restore or recover my CONTACTS and my CALENDAR.

Apple Customer Support FAILED

Me, too! I have a “New” iPhone 13 which is not even a year old and …

Apple Customer Support actually misinformed me by instructing me to do a Software Update 18.0.1 and DID NOT warn me that I would loose my CONTACTS and my CALENDAR.

Now, I desperately need Apple Customer Support which appears to be non-existent to recover my CONTACTS and my CALENDAR.

Same issues for me. Now, I am so very upset as lost ALL my Contacts and ALL my past present and future Calendar appointments simply because without any warning of the consequences was I instructed by the Apple Customer Support “Lisa” to do this UNACCEPTABLE Software Update 18.0.1 😭

Wanted to throw my displeasure into the ring on this. I've been researching for two days on what happened. I've been using iTunes on my PC for years to sync my calendar and contacts with Outlook. It's how I've wanted to do it mainly due to company reasons. I just realized this the other day that the calendar is not updating between my iphone/ipad and my Outlook. The Contacts update just fine as they always have.

I've tried several things but nothing I've read is working, and I don't want to flip that switch to iCloud to Merge and lose all my data. I did that with my contacts, and thankfully I had a backup to restore my Outlook back to normal.

Similar issue with everyone here.

Have been syncing my Outlook contacts and calendar from my Windows PC to my iPhone successfully for years.

Updated to iOS 18.1 and can no longer sync even after unchecking SYNC CALENDARS, checking it, and overriding iPhone several times.

Simply does NOT sync any more.

Has ANYONE had any success with this?

Well, I keep on trying. I did a repair of the iTunes AND Microsoft 365. Syncing my phone, the calendar items do not sync.

Just now, I connected up my iPad after updating it to 18.1.1. Contacts AND Calendar items synchronize between my Outlook and my iPad. I entered an item in Outlook, and I entered an item in my iPad calendar. Both items sync perfectly.

I can't comment on the version my phone is running or this post will get deleted. My phone is an iPhone 16 Pro Max, so I'm wondering if anyone has the 16 Pro running the latest 18.1.1 OS and having any luck syncing both the contacts and the calendar items.

I have compared, side by side, the settings on my iPad and iPhone, and I cannot find any differences between them. Major difference is the OS versions. Note, I have been synchronizing my iPad and Iphone for years with iTunes, and I find it odd that it is only the Calendar having issues. Especially confusing now that I know my iPad is perfectly fine.

I really, really, really X's infinity, do not want to reset the phone and go through the hassle of getting things to where I have them now.

You have no idea how badly I wanted your solution to work for me! Sadly, I must report it did not. Here is my longwinded reply. Let me first say that both my iPhone and my iPad use the EXACT same settings with the only difference being the OS versions. iPhone does not work for calendar - works for Contacts; iPad works for both Contacts and Calendar.

Here are the accounts that I have:

My main account is the Destcom, which is my work account. The Gmail is my personal account that I only use for email and nothing else. The others are the same, email only. The iCloud I use for nothing related to email, contacts, or calendar.

My gmail account shows me this, and note the options. Showing this just to show the options for contacts and calendar are toggled off:

This is my main account; you will see there are NO options to toggle contacts or calendar:

However, for more years than I can remember, I've always synchronized my contacts and calendar through iTunes, and this is the setup I've had forever:

There is an obvious connection between iTunes and Outlook since all my contacts update correctly. Without reverting my phone back to 18.1.1, I can only assume this might be an OS version issue. I might possibly try doing this very thing this weekend, but it's always a pain to me when I've had no issues up until OS18.

Extremely disappointing : all my events are" misplaced repeating events show = sign everywhere : I mean I did this upgrade accidentally I REGRET SO BADLY. THE CALENDAR IS NOT A BONUS. It's essential , your product is NOT ESSENTIAL IT's a luxary . I DON'T understand why your so careless with customers : Would it be pic app / game app / I can understand , but the calendar , to wake up and see this mess after over 15 years of impeccable service and us counting on you for the price we pay : DONT DO AN UPGRADE so soon . We can wait. And do your job as we try to do ours! As this calendar issue is gonna be costy at least for me.

Thanks but didnt work - I thought I'd lost all my calendar appointments but as you say they repopulated - but nothing new since the update was installed.

Apple, do you read this feedback? I doubt you care, but just in case: how could your software people and the checkers be so monumentally incompetent as to screw your customers over so badly with an upgrade? My iPhone is now half useless. (And why can't customers check server settings etc to diagnose what's wrong?)

Same issue here; Exchange no longer syncs. Could this have something to do with higher security settings in 18.1? I noticed when I try adding a new Exchange account a message appears saying that “your Exchange administrator will have access to your device and the ability to delete data from your phone.” Could it be that I have a security settings turned on that’s blocking the Exchange account?

This worked! I tried four different solutions prior to this. After it finally synched, my invites showed up in my inbox and I’m finally seeing a couple appointments I was missing. Thank you, Kimowaggs!!

Kimowaggs, thank you! this worked for me, very pleased! (A couple times you wrote the word calculator in your instructions when you meant Calendar 😆) I didn’t even need to restart my phone. You rock!!