Use Zimbra Email Account Migration tool-a conversion utility that helps you to Zimbra Export to different popular file formats like MSG, PDF, PST, MBOX, EML, VCF, ICS, HTML, RTF, DOC, Office 365, Exchange, Thunderbird, IMAP Server, Outlook.com, Gmail etc. along with all email attributes and attachments. Zimbra Email Account Migration tool has capability to run on all Windows operating Systems 11, 10, 8.1, 8, 7, XP, etc. For exporting Zimbra desktop message to desired format Zimbra installation or any other email application installation is not compulsory. Get more info with its free trial version which supports Zimbra email account migration, but is limited to 25 items per Zimbra folder only. For Zimbra email account migration in batch, you have to purchase license edition of this tool.