Outlook Client Calendar Attachments to External Recipients missing

[StevieH]

When users of a Shared Mailbox create a Calendar entry with Internal/External recipients, when they include attachments, the internal recipients receive the attachments in the calendar, but they are removed for external recipients.

Requires the organiser to send a follow up email with the attachments.

Just curious to where the limitation is that is preventing the attachments in calendar from going to external recipients

[#2 · Accepted solution]

@StevieH 

It would seem that this may reside with the recipient configuration & not with my sending details.

I was able to successfully create, attach & send a calendar invite to two external domains.
Then subsequently modify, attach additional & send a calendar invite to the same external domains.
Each time the calendar event was received with attachments.
Checking further & this article
Set-CalendarProcessing