Try changing the default from what it is now to anything else. Then go back into Zimbra Desktop and see if the option is now available.
Be forewarned though, that even if you can get it set as the default email application it won't do everything you might think it would. It should work for "mailto:" links, but won't work for things like "File --> Send To --> Mail Recipient" within Office applications.
You might want to search around the forums and bugzilla. There are other posts that discuss this issue, and I believe there are a few open bugs regarding this as well. |