Fix Google Calendar sync errors

Common Google Calendar sync problems

Most Google Calendar sync problems fall into five groups. Find the symptom that matches yours and work through the fixes in order.

Error 1: Events not appearing

Symptoms

• New events don't show up on other devices
• Changes take hours or days to sync
• Some events appear, others don't

Solutions

Check your internet connection. Google Calendar needs a connection to sync. Make sure you're on WiFi or mobile data.

Refresh the app

1. Open the Google Calendar app
2. Pull down to refresh
3. Wait for the sync to finish

Check sync settings on Android

1. Go to Settings > Accounts > Google
2. Make sure Calendar sync is on
3. Tap "Sync now"

Error 2: Duplicate events

Symptoms

• The same event appears several times
• Duplicates appear after syncing with other apps
• Deleting one duplicate brings the others back

Solutions

Find the source. Check which app is creating the duplicates. Usually two tools, or the same tool twice, are copying the same calendar.

Remove duplicate calendars

1. Go to Google Calendar settings
2. Look for the same calendar subscribed more than once
3. Remove the extra copies

Use a sync tool that tracks what it creates. Caltsu stores the ID of every block it creates, so it updates the existing block instead of adding a new copy.

Error 3: Calendar not syncing with Outlook

Symptoms

• Google Calendar doesn't update in Outlook
• Outlook events don't appear in Google Calendar
• Sync stopped working suddenly

Solutions

Reconnect the account. If you added your Google account to Outlook, remove it and add it again. Outlook asks you to sign in to Google and approve access once more.

Check the subscription URL. If you subscribed to Google Calendar in Outlook with a link:

1. Make sure you used the secret address in iCal format
2. If you reset that address in Google, the old link stops working, so copy the new one
3. Remove the subscription and add it again

Use a two-way sync tool. A URL subscription only goes one way, and Outlook refreshes it on its own schedule. For two-way sync between Google and Outlook, Caltsu adds Busy blocks to both calendars. See how to sync Google Calendar with Outlook.

Error 4: Sync delays

Symptoms

• Events take hours to appear on other calendars
• Changes only show up when you refresh by hand

Solutions

Know how subscriptions refresh. The app that subscribes to an iCal URL decides when to fetch it again, and that can take hours. You can't make it refresh faster.

Use push-based sync. Caltsu listens to Google push notifications and Microsoft Graph webhooks, so it picks up changes as they happen instead of on a polling interval.

Error 5: Permission errors

Symptoms

• "Cannot access calendar" errors
• Permission denied messages
• Calendar appears empty after connection

Solutions

Grant the calendar permissions

1. Go to Google Account > Security > Third-party apps
2. Find the app having issues
3. Make sure it has calendar access. If not, remove it and connect it again

If you use a Google Workspace account, your admin may need to allow the app first. See how to allow Caltsu in Google Workspace.

Check calendar sharing settings

1. Open Google Calendar settings
2. Select the calendar having issues
3. Check that the person or app has the permission it needs

Preventing future sync issues

• Sync each calendar with one tool. Two tools copying the same calendar is the most common cause of duplicates.
• Keep your calendar apps updated.
• Check now and then that a new event shows up where you expect it.

When to contact support

If you've tried all of the above and still have issues:

• Check the Google Workspace Status Dashboard
• Look for known issues with your calendar app
• Contact the app's support team. For Caltsu, email support@caltsu.com