Before all things, who use Outlook 2016 for Mac?
Because, I'm not this error on Zimbra 8.7, but only with this 8.8.10 version.
I explain, as you know, when you want to move a message to a specific folder, you have to use a rule, that you create, when you make a right click = > rules = > Create a rule, and when it is created (on version 8.7) the information Part well on the server, but under the new version Zimbra, error message:

I have a different message when I want to see if it's recorded, Tools => Account => Rules => click Account

Surely one of you, has already had this problem, which as even important.
Mz