Hello everyone, new Zimbra user, currently pleased with the product but having 1 problem

First off my setup

Zimbra 8 Installed on Ubuntu 12.04LTS 64 bits
Having one domain, lets call it test.local
Having 3 users on that server
Using a trial licence (60 days) before we deploy it at our client
Everything is in a lab environment so no internet
Having a server with bind 9 to act as our DNS

Using the Website https://mail.test.local works #1 can send receive email all is fine
-Installed Office 2010 32 bits on my Windows 7 32 bits clients and then installed the Outlook Connector from the Admin page of my Zimbra Server

Now when i click to add an account I cannot

So in server i type mail.test.local (i can ping it so the resolving is fine)
I then click SSL (since we go with https on the site)
username i type Whippet@test.local (this is a created account on my server)
and then the password

I then click on no proxy cuz i think we don<t have one.

Now when i click OK it says

The Certificate is self-assigned or the certifying authority is unknown to this computer

If i uncheck the use SSL

Your account cannot be validated by the Zimbra Server

IF i click cancel Outlook 2010 closes

Anything i can try?