Import .ics calendar file into Thunderbird on Windows
- Click on the three vertical lines, then select Tools, then Import.
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- Choose the Import from a file option and click on the Continue button.
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- Choose Import Calendars, then click the Continue button.
- Browse to find the file and click Open. Then click Continue.
- Click Continue to choose where to import the calendar.
- Click the Start Import button to finalize the import, or the Back button to perform changes.
- Click Finish.