My exchange calendar disappeared. Any ideas?

Hi mary_w,

We use MS Outlook Exchange and I was told by a coworker to do the following. Look at the meeting requests with attachments by size of the file. Remove any attachments from the meeting requests that caused the file size to be greater than 1MB and save them offline. This is even for meetings that are in the past. Once they are all less than 1MB, power your iPhone or iPad down completely. Turn it back on an viola they should be all back. It worked for me.

Good Luck

On your iPhone, go to Settings > Mail, Contacts, Calendars.

Select your Exchange account.

Turn Calendars off for over the air syncing. A warning message will be provided indicating this will remove the calendar and all events synchronized with the Exchange server.

Follow this by turning Calendars back on for over the air syncing to reset the calendar with the Exchange server and re-download all calendar events from the server.

Mine is doing the same thing. I have been connected to exchange over the air with nor problem since I first got the iPhone 4. Now in the past week the calendar starting getting out of date. I tried removing and re-adding the Calendar (same as Allan's suggestion above) and now there are no events at all. I have noticed that new invites are appearing - so it's talking with exchange (and email is fine) but all exsiting calendar entries are gone!! How do I force a full sync? Is there a way to get it working again? I updated to the latest OS version as of today.

Same issue within my organization. Connected over EAS, calendar items were all there for the last year or so. Now they disappear, reappear, and disappear again during the day. Sometimes recurring meetings stay there longer before they disappear. Looks like this is a serious bug, either on the iOS or Exchange side.

Same issue in my organisation. All iPhones are connected via Exchange Active Sync. Calendar was OK since May this year, but the problems started around 2 - 3 weeks ago (the user hasn't noticed the problem then). There are duplicate Calendar entries, I've seen one Calendar entry (not synchonised to Exchange server) disappear on the iPhone after I scrolled the Calendar list up and down. Seroius issue with Calendar, either on Exchange server side or on iPhone.

I am getting reports from my users of missing meetings. Not all of the calendar entries are missing, just a meeting here an there. The users are running iOS 4.3.3, using EAS to sync with Exchange 2007 and the missing meetings seem to be single occurrences of recurring meetings that have been changed - time change, room change, someone added. Re-syncing calendars using the method mentioned by Allan does reload all the meetings onto the phone - until another meeting gets rescheduled. The users never know if a meeting has been cancelled or just disappeared. Of course the problem seems to be more prevalent among the corporate VPs as they are more likely to have a meeting moved and to let me know when there is a problem. The users having problems are all syncing multiple devices (iPhone and iPad) and the problem seems to occur more often on the iPhone then the iPad, not sure if the multiple devices is contributing to the issue or not. I have the same setup but with few recurring meetings that get changed and thus haven't experienced the problem. I could sure use a fix for this.

Hi there,

same issue. Some calendar entries wont appear in the iphone. I can´t reproduce this issue but iam very concerned about it. We are using Exchange 2010 and this seems to be an IOS issue. Deleting the sync and reactivate it dosn´t do the trick.

It would be great if someone from the apple business support team could help, because some of our users have already missed some serious meetings!!

I am also having this problem. I am a user and evidently I am the only user out of about 100 iPhones within our company that is having this problem. It started about two weeks ago. I left town for a week and came back and started having problems that are getting worse and worse. I downloaded the newest version of iOS 4.3.5 last week and it did not help. My calendar will partially load and then disappear and then begin to reload a differently color. After a couple of minutes it will disappear again and begin to reload again. My email and contacts work fine. I have more meetings than most other users. I believe the problem must be with iOS because Exchange and activesync would have nothing to do with the colors changing. I have requested that our IT folks delete my activesync account and recreate it because I have tried everything I can think of. I reloaded by iPhone from my computer and did not restore the phone from the previous backup. I did not add any music or other media or apps. I only turned on activesync and it did not solve the problem.

Same with me! ...IOS 4.3.5 (8L1)

The funny thing is that each time that the calendar starts disappearing and re-appearing, the color that is used by iPhone to show the meetings on my selected exchange profile changes...

Am I the only person that experiences this kind of symptom?

Bye, Ingalli

Seeing the same issue as Ingalli - with multiple Exchange servers and multiple (but not all) users. Have yet to determine the cause or a workaround.

For the benefit of anyone watching/finding this thread, we did find a solution.

The underlying issue was a corrupt calendar appointment (with attachment). I'm not sure how it go that way, but if I attempted to open the appointment in Outlook, I would get an out of memory error. Deleting this appointment fixed the iPad sync.

Unfortunately, other than a cumbersome search, I don't know a good way of finding exactly which calendar item is to blame.

Try running CalCheck on the Outlook profile in question, you may find these corrupted events easier: http://blogs.technet.com/b/exchange/archive/2012/02/22/calcheck-the-outlook-cale ndar-checking-tool.aspx.

See the discussion happening around this issue elsewhere for info: https://discussions.apple.com/thread/1918410?start=75&tstart=0