I have been forwarding calendar events to my other email accounts in order to keep my various calendars in sync. I have recently discovered that calendar events sent to any Office 365 account (I have 3) that is then forwarded to an Exchange Server account (I have 3) will not show up on the Exchange Server calendar. I am able to accept these calendar invites on my laptop, but they will NEVER show up on the Exchange Server calendar.

Please advise as it is now clear that my calendars are not in sync unless the original invite is sent to one of my Exchange Server accounts.