Why is My iPhone Calendar duplicating events

Event duplication is usually caused by another calendar syncing process running at the same time as Cirrus Insight Calendar Sync. We'd recommend connecting with your Salesforce admin to see if your org is currently using (or has used in the past) any other calendar syncing applications such as Salesforce for Outlook, Ebsta, Yesware, or Appirio Cloud Sync. 

Those processes need to be completely disabled, uninstalled, and blocked in Salesforce to avoid event duplication. One area that's often overlooked is Connected Apps Oauth Usage under the Manage Apps section in Setup. Salesforce provides some helpful information about revoking/blocking apps here:

"Salesforce - Monitor Usage for Connected Apps"

If you don't find any other calendar syncing applications within Connected Apps Oauth Usage, please contact Support and provide the following:

1. Screenshot(s) of all apps within Connected Apps Oauth Usage
2. Screenshots of an example duplicated event

The duplicating events issue may be related to a sync glitch or to the fact, that Calendars 5 displays the same events from the built-in calendar app on the iPad/iPhone along with your Google account data.

Follow the steps below to remove the duplication:

iPhone

1. Tap  .
2. Tap  .
3. Tap Local Calendars.
4. Turn off Google Calendars.

iPad

1. Tap  .
2. Tap Local Calendars.
3. Turn off Google Calendars.

In this case Google Calendar attached to the iOS calendar app will be removed from Calendars 5.

If you still can see some events duplicating, check the list of all calendars under  the icon and uncheck the calendar copies.

If the issue persists, please contact our support team. For this:

1. Go to  .
2. Tap Support.
3. Send Feedback.

A support log will be attached to your email. It will be also very helpful if you describe the situation in detail so our Support team could provide you with a solution.

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An old friend messaged me: his wife’s OS X Calendar app was making duplicates for every entry. She’d create a new entry, fill it out, and then within a moment a duplicate labeled “New Event” appeared. The calendar is synced via iCloud, and it seems like a problem that would be related to that.

Because iCloud sync is live, whenever you create a new event in a synced calendar, the Calendar app pushes the initial raw entry on creation to iCloud, and as you modify it, those updates are sent. It would seem, in this case, that the initial entry is created in one step, and the modified version has a different underlying bit of tracking data that makes it appear like a distinct appointment.

That leads to the initial New Event synchronizing back to the creating Calendar app (and all other synced calendars). Why is this happening? So far, I don’t have an answer for my friend’s wife, but if you’re having a similar problem, here are strategies to try that have worked for other people.

A New Event can ripple across sync and wind up duplicated—but why?

Refresh calendars. Apple suggests choosing View > Refresh Calendars in the Calendar app, which performs a force synchronization. If there’s a lag, this can bring calendars back into sync.

Log out of iCloud on connected devices and back in. This is an extreme and irritating move to have to make, because if you’re using iCloud for a number of services and for syncing, you have to answer questions when you log out about what to keep and what to delete. (Typically, keep everything, and it will sync and merge back when you log back in.) Many users in forums have found this solved duplicate entry problems.

Check your lag across devices. If you have the same calendars syncing on multiple devices to iCloud or other services, like Google, it’s possible that you’re having a disconnect among them. You create an event on your Mac, it syncs over iCloud to an iPhone, but when you update the original entry, the iPhone acts as if it created the event in the first place. Calendar-sync services are designed to avoid this particular problem, but if you can have all your devices in one place and watch whether this occurs, it might reveal the cause of the problem.

Readers, have you had this problem? And if so, was it consistent and were you able to fix it? We’ll look forward to more suggestions in the comments.

Ask Mac 911

We’re always looking for problems to solve! Email yours to including screen captures as appropriate. Mac 911 cannot reply to email with troubleshooting advice nor can we publish answers to every question.

If you use your iPhone's Calendar app to keep track of your daily schedule, duplicate calendar entries can make your day look twice as busy as it really is. In many cases, you can simply delete the duplicate entries on your iPhone. This is the fastest solution if you have accidently accepted an invitation on your computer and again on your iPhone. In some cases, duplicates can be caused by two different calendars syncing to the iPhone, creating dozens if not hundreds of extra entries. If this is the case, you can hide or delete the specific calendar within the app that is causing the problems.

Deleting Duplicates Entries From the iPhone

Launch the "Calendar" app on the iPhone. If there are only a couple of duplicate entries, you can delete them quickly.

Locate a duplicate entry and tap it with your finger.

Tap the red "Delete" button to remove the duplicate.

Hiding and Deleting Duplicate Calendars

Examine the iPhone's Calendar entries to determine if specific calendars are causing duplicates. For example, if you have and "Outlook 1" and "Outlook 2" calendar, these may be the same calendar imported twice.

Tap the "Calendars" button in the upper left corner of the screen.

Tap the duplicate calendar to remove its checkmark. This hides that calendar's entries. Tap the "Done" button.

Examine your calendar events again to ensure you are not missing any important events while the duplicate calendar is hidden.

Delete the duplicate calendar if desired by navigating back to the Calendars screen and tapping the blue "Arrow" on the right. Scroll down the screen and tap the red "Delete Calendar" button. The calendar is removed from the app.

If you see duplicate calendars or events on your iPhone, iPad, iPod touch, Mac or PC after setting up iCloud Calendar, follow these steps.

To hide and unhide calendars in the Calendar app on your iPhone, iPad or iPod touch:

1. Tap Calendars.
2. Select or deselect the calendar’s tickbox in the Calendar list to show or hide a calendar’s events.

To hide and unhide calendars in the Calendar app on your Mac:

1. Select View > Show Calendar List.
2. Select or deselect the calendar’s tickbox in the Calendar list to show or hide a calendar’s events. To show or hide events from all calendars, press the Command key while you select or deselect any calendar’s tickbox.

To hide and unhide Holidays and Birthdays in the Calendar app on your iPhone, iPad or iPod touch:

1. Tap Holidays and Birthdays to include national holidays and birthdays from Contacts with your events.
2. Select or deselect Show Holidays or Show Birthdays calendar.

To hide and unhide Holidays and Birthdays in the Calendar app on your Mac:

1. Select Calendar > Preferences, then click General. 
2. Select or deselect Show Birthdays calendar.

If you see multiple birthday events for a contact on your iPhone, iPad or iPod touch, check if you have more than one contact card for that specific person. Open the Contacts app, tap the Search field at the top, then enter the contact's name. If you see multiple results for the same contact, tap the contact, then tap edit to manage, delete or consolidate their contact information.

To delete local calendars on your Mac:

1. Make a copy of your iCloud calendar data.
2. In the On My Mac section, click the calendar you want to delete. 
3. You can delete the calendar in two ways:
   • Choose Edit > Delete.
     
   • Right-click and select Delete.

To delete local calendars on your PC:

1. Make a copy of your iCloud calendar data.
2. In My Calendars on your PC, right-click the calendar you'd like to delete and choose Delete Calendar. Outlook won't let you delete the default Calendar, but you should be able to remove other calendars that you have permission to delete.

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