Exchange Server 2013/2016 and Exchange Online send RTF messages in HTML format
Configure Exchange Server 2013/2016 and Exchange Online send RTF messages in HTML format
Open Exchange Management Shell
run the following command
Get-RemoteDomain | Where {$_.TNEFEnabled -ne $false}
For each Remote domain, please run the following command
Set-RemoteDomain -Identity Default -TNEFEnabled $false
Restart the windows service ‘Microsoft Exchange Transport’
