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Why doesn’t my email sync with my calendar?. How do I synchronize Windows Mail with Google Calendar?. How do I sync my Gmail calendar with Windows 10?. Remove the problematic email accounts from your calendar and add them again. Enable the privacy settings so that the application can access your calendar data. Changing the synchronization settings for each of your email accounts. Allow the Calendar app via the Windows Firewall services. How to resolve the Google Calendar/Mail Not Syncing problem on Windows 10?.
Why is Google Calendar/Mail not syncing on Windows 10?.