In classic Outlook there is no single “Google Calendar integration” button. Google calendars are added either as an Internet calendar subscription or by importing an .ics file.
For a live, updating view of a Google calendar in classic Outlook:
- In Google Calendar, go to My calendars → hover the calendar → Settings and sharing.
- Scroll to Integrate calendar and copy the Secret address in iCal format URL.
- In classic Outlook, open the Calendar.
- On the Home tab, select Add Calendar → From Internet.
- Paste the iCal URL and select OK, then choose Yes to subscribe.
This subscribes Outlook to the Google calendar so it stays updated.
To import a one‑time snapshot instead:
- In Google Calendar, open Settings and sharing for the calendar.
- Under Calendar settings, choose Export calendar and extract the downloaded .zip to get the .ics file.
- In classic Outlook, select File → Open & Export → Import/Export.
- Choose Import an iCalendar (.ics) or vCalendar file (.vcs) → Next.
- Browse to the .ics file, select it, then choose Open as New.
This imports a static copy of the Google calendar into Outlook; it will not auto‑update.
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