Once Pidgin has been downloaded and installed, run the application
You will be presented with a Welcome screen. Click Add.
Basic Tab: Protocol=XMPP
Basic Tab: Username=Your Zimbra Server username. For Example, if I were email@example.com, it would only be ddemouser. DO NOT use a full e-mail address.
Basic Tab: Domain=The portion of your e-mail address that comes after the @ sign. For example, if I were firstname.lastname@example.org, the domain would be testzimbra.com.
Basic Tab: Resource=Home (Enter whatever you wish, this identifies your unique endpoint.)
Basic Tab: Password=Your Zimbra Server Password.
Basic Tab: Remember Password=User Preference.
Basic Tab: Local Alias=The nickname for your account.
Basic Tab: New Mail Notifications=Unchecked.
Basic Tab: Use this buddy icon for this account=You have a choice of which avatar you wish others to see.
Advanced Tab: Require SSL/TLS=Recommended, if you use https instead of http, check this box.
Advanced Tab: Force old-style SSL=Unchecked.
Advanced Tab: Allow Plain text authentication=Not recommended, but if your server uses http instead of https, then check this box.
Advanced Tab: Connect Port=5222
Advanced Tab: Connect Server=The FQDN or Reachable IP of the Zimbra server. If you do not know this, you should ask your system administrator. If running your Zimbra server behind a NAT, you can use the NATted IP Address only if it is usable within a network for which the Zimbra server can be seen. NOTE: Using an IP may result in future issues if your Zimbra server IP Address changes. Using the FQDN is the preferred best practice.
Advanced Tab: Proxy Type=If you connect to your Zimbra server through a proxy, you should choose this. This DOES NOT apply to the Zimbra proxy, if installed.
All Tabs: Create New Account on This Server=Unchecked.