Firstly get the freeware edition of PST to Zimbra Converter by clicking on the download button-
Win 10 & all below version
First Step: Open PST to Zimbra Converter software
Second Step: Click on the "Select PST" button from software toolbar. The following screen appears-
Click on the "Browse" button and select your rquired Outlook PST file.
Software automatically starts the recovery process and show your complete list of folders in tree like hierarchy in left panel of software as below screen-
Now check the preview of recovered PST file items preview and go ahead for conversion from PST to Zimbra TGZ.
Third Step: To import PST file to Zimbra, Click on the "CONVERT" button from toolbar. The following screen appears on your screen-
Now here you have to choose the file saving location and click on the "Convert Now" button.
Once software completed the conversion, then show you confirmation as below screenshot-