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Office365 and subscribe via ics

8218967 shared this problem 4 months ago

I've subscribed to a publicly shared Office365 calendar (*ics), but the Mailbox calendar never imports the calendar items; additionally, when I refresh the calendar from Mailbox' Calendar app, it throws the following error:

ErrorThe supplied recurrence rule is invalid. Please correct the rule and try again.

So, is it something about Mailbox ... or Office365 ... that prevents the calendar from being refreshed?

Comments (2)


The error makes it sounds like the iCalendar file is malformed or has a malformed or unsupported reoccurrence rule. You can try checking your iCalendar file in an online validator and see if that gives you more detailed information about the problem.


I am having the same issue. The validator flags 16 instances of the following error:

"UID value is not unique, duplicate found near line # 214Reference: RFC 5545 Unique Identifier"

It seems as though this error breaks mailbox.org calendar subscription logic. However, I am able to successfully subscribe to this ics link using native macOS Calendar and iOS Calendar.