On-prem Exchange 2016 on Windows 2012 R2. On-prem SonicWALL firewall.
Trying to add an Outlook Addon from Barracuda Network in EAC, but getting the "error. The app couldn't be downloaded" when trying to install. No event log indicating what the issue is. Based on some of the forum postings, sounds like I need to enable a http/https rule to allow the traffic, however, I can't find any information on the steps to enable such rule. Is this to be done on the Exchange server or on the SonicWALL firewall?
Appreciate any guidance in this matter. Thanks in advance.
Roget Luo