Download Zimbra Desktop: http://www.zimbra.com/products/desktop.html
1. Open the downloaded file:
2. Click 'Next':
3. Accept License Agreement, Click Next:
4. Choose a path to install the application in and click Next:
5. Choose whether or not to create a desktop icon and click Next.
6. Leave Launch Yahoo! Zimbra Desktop checked. Then, click Finish
7. Click "Add new account":
For account type, select Zimbra
Create a description for this account in the Account Name field
Enter your full email address and password
For the mail server address, please ask your System Adminstrator or open a help desk ticket.
Select your preference for synchronization settings, which is how often the program will check for new mail.
Click Validate and Save
Note that the first synchronization may take up to several hours to complete depending on how much data is in the account. However, you may start using this account immediately
For information on using Zimbra Desktop please reference the Yahoo! Zimbra Desktop End User Guide.
Also please feel free to take a look at their F.A.Q.
If you require further assistance, please submit a new ticket at https://enterprisesupport.01.com/