Comment 118 for bug 849416

In case somebody needs a simple workaround just to deal with the very occasional Outlook user, here's what I did:

1. View message source; scroll down to "Content-Type: text/calendar" section
2. Copy the block of base64 text and decode it. (On Linux, I use base64 -d; there are also online decoders like https://www.base64decode.org/ ).
3. Save the resulting text (should start with "BEGIN:VCALENDAR" and end with "END:VCALENDAR") into a file. E.g., event.vcs.
4. Open up Google Calendar. In the left margin, click on the "Other calendars" menu and pick "Import calendar."
5. Select your file and click "Import". It should say, "Processed one event. Successfully imported one event."

After that, you should have the event on your calendar. This definitely isn't optimal, but it seems better than having to email back a client and ask them to send you details in plain text.