You can use third party tool like Zimbra to Gmail Converter that can quickly transfer Zimbra file to Gmail account without facing any hassle. This software also convert Zimbra files to Gmail and other file formats such as PST, MBOX, MSG, EML, EMLX, PDF, HTML, etc. It extracts all the essential mail components like To, Bcc, Cc, Sent, From, Received, Attachments, etc.
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