I am new to using Zimbra. As listed in my details I am running the Zimbra Desktop 7.1.4 GA (build 11299).. on Windows 7.

I have set up some filters. And I want to run those filters on the existing mail already imap'd in. But I can't find ANY way to do it.. and it's giving me a headache.

In the Zimbra Desktop Help it says the following in the "When filters are applied" section:
You can also run the filter rules over an existing set of mail items. In Mail Filter Preferences, the Run Filter button allows you to select multiple filters to run against selected mail folders.

Where is the Mail Filter Preferences? I don't see anything in Preferences or Filters. There's no option when you right click on a folder containing mail you want to filter. There's no "picture" of what this elusive button looks like. I can't find anything, and I am not some noob who doesn't know how to use programs. I've used a variety of programs, in a variety of ways. There are features I want to give a go in Zimbra to see if I like it.. but I need to filter the mail I have already. I don't want to manually do it.