Problem: G Suite Calendar Events that Pass Through Office 365
Microsoft is investigating an issue where calendar events that begin in Google’s G Suite Calendar, go to Office 365, and return to G Suite may not display properly in Google Calendar. Office 365 calendaring is not affected by this issue.
Specifically, Cornell G Suite users may experience spoofing or fraud warning banners, valid calendar-related email going to their spam folder, or in rare cases, senders receiving bounce messages for email with attachments or Calendar events originating from Gmail or G Suite environments. The issue in Office 365 is being triggered by .ics files attached to Google Calendar Events.
Microsoft is expanding their testing of the potential fix for this issue to ensure it resolves the problem without introducing new unexpected behaviors.