been running zimbra server for ages, with thunderbird as a client, but the customer wanted shared calenders and lightning was an administrative nightmare to set up.
I've tried the zimbra desktop but its a bit flakey and doesnt handle the email side of things as well as the customer wants.
ZD has lost its config several times & emails appear to become empty and the account needs to be reconfigured.
Can I run a trial of NE on my server - eg upgrade to NE 7.1.4 and see how it goes with outlook as a client? the servers done nothing but run OS edition since v5 now on v7.1.2