How to Switch Calendar Sync Tools Without Creating Duplicates

Hand over each copying job from the old tool to the new one without running both into the same destination. For example, list the rule that keeps personal busy time on your work calendar, then plan how its old copies will be removed before the replacement creates new ones.

Sources, destinations, and existing copies

Write down each source, destination, direction, and service involved. Include desktop add-ins, automations, feed subscriptions, and manual blocks, not just the service you pay for.

Identify which events are originals and which are copies. Note any title prefix or dedicated destination calendar that helps distinguish them. A Busy title alone may not be enough.

Record the fields and filters in your busy-only copying settings. If the old setup hides personal notes, apply that privacy choice before the new tool creates any copies.

Back up before cleaning up

Export the important original calendars using the provider's supported method. Keep the untouched files and date them clearly.

For Google, export through the calendar website on a computer. Its export guide explains permissions and download options. Apple Calendar on Mac also offers individual calendar exports and a different full archive format; see Apple's guide.

Keep the checked backup for recovery. Importing it into a calendar already receiving sync copies can add another set of events.

Stop the old writer while it still has access

Read the old service's cleanup and disconnect instructions. Disable the relevant copying rules or profiles and decide whether their destination copies should be removed.

Where a service offers cleanup, use it before revoking provider access. Once permission is gone, it may be unable to remove the events it created.

Check the destination website afterward. Stop the service's copying rules explicitly. Deleting its phone app or closing a browser leaves server-side rules running.

If the old tool cannot identify its copies, work from your inventory and sample events. Do not bulk-delete appointments merely because their titles match.

Start the new service with one path

Connect the required accounts and begin with one source and one destination. Recreate the necessary privacy controls before enabling a wide set of copies.

For an Avum replacement, create one Sync Rule for the original source and destination. Reapply its privacy settings before enabling it. Count the Google, Outlook/Microsoft 365, iCloud, or CalDAV accounts and directional rules the complete arrangement needs; ICS sources are read-only. Choose a plan that covers that count.

A CalDAV calendar intended as a destination needs write access. An ICS feed cannot be a writable destination. If the old workflow used an authenticated account, do not downgrade to a public feed simply because it appears easier.

Check the handover with a few events

Create a timed test event at the source. Check the new destination copy, move it, then cancel it. Include a recurring exception and an all-day event if those occur in your schedule.

Inspect the destination through its own provider website and check the actual scheduling or booking view. Include copied fields and work availability in the handover checks.

If duplicates appear, identify overlapping views or genuinely duplicated events before adding more rules.

Remove obsolete access last

Once the new arrangement is working and old copies are handled, revoke the old service's access through the provider's supported settings. Google documents this in its third-party access guide.

Remove old desktop profiles too, particularly on computers you do not use daily. Keep the handover notes so a future unexplained copy has a traceable source.

If you decide against a replacement service, use a native combined view or maintain the few manual busy blocks you need.

Ready to try a carefully scoped replacement sync? Start your free 30-day trial with Avum today.