I know outlook 2010 will not be supported in 2020 but for now I have a client that uses it. We migrated our exchange server over to 2016 that's when she started to have issue with sending from her "HostGater@hostgater.com" IMAP email account, they cant send our receive from it but can send receive from the user@exchange.com account. I added a new outlook profile HostGater@hostgater.com IMAP email only and I was able to send\receive but when I added the exchange email user@exchange.com to this profile it didn't start re-downloading the exchange emails they were already downloaded and the hostgater@hostgater.com email broke. Do I need to check the box for the exchange login when starting outlook or do I have to upgrade to outlook 2016?