First, launch the software on your Windows PC. Once downloaded, the first screen of the software will be shown as:
Now click on Add Files to add TGZ files on software panel. Here you will get "Add Files...", "Add Folders..." and "Add Extracted Folders..." options to load multiple TGZ files as per your requirement.
Once you have selected the TGZ files, the software will start the scanning process and after analysing, extracts all its folder items on the left software screen.
Once the files are loaded on the software, they are listed on its left screen. If you want to delete them from the software pane, use the Close Files button.
If you click on the required folder, all the its file list will appear immediately on the right software pane. Click on the email you want to view and all its data will appear in the Preview section.
Now, click on Export button and select the desired saving option for converting Zimbra mailboxes.