Conference calls invites not going to all participants

[mmamakas]

Hello all,
Weird issue-- when sending conference call invitations not all users are getting the invite by email. They get the reminder emails, but not the original. This is happening with both the built in SMTP server and Office 365. I can see the sent message in O365, and sure enough many of the recipients are missing.
Running V16 on Debian.
Anyone have any thoughts?

 

[cobaltit]

Sounds like filtering on the recipient side.

 

[mmamakas]

It isn't filtering on the recipient side. If I invite 15 people, maybe 6 go out. I see only 6 transmitted. However, all 15 will get the reminder follow up emails to all.