After installing the Zimbra Connector for Outlook, you must create a profile that outlook uses to logon to you Zimbra mailbox. On a fresh install, the Zimbra Connector for Outlook installer will create a default profile named "Zimbra". You can use this profile or create a new one.
You must not add a "Zimbra" service to an existing profile. IE, you must NOT logon to outlook using an existing IMAP profile and select "tools->email accounts->add a new email account" and proceed to configure your Zimbra email account. If you do this, the Zimbra service will not be the default store and will cause unexpected results.