If anyone is required to transfer Thunderbird emails to Gmail, then using the most successful software that name is "eSoftTools Thunderbird to Outlook Converter". It can export Thunderbird to various file formats such as NSF, Msg, Emlx, Eml, HTML, Gmail, Yahoo, Office 365, and Gmail. It can convert single or multiple thunderbird files at once without creating any problem. This tool support all version of Windows and MS Outlook.
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