If you want to learn how to transfer Thunderbird emails to Gmail, first download the eSoftTools MBOX converter app. It has outstanding features that allow you to quickly pass Thunderbird emails to Gmail without wasting time, and it is consistent with MS OUTLOOK 2019, 2016, 2013, 2010, 2007, and 2003. This program transforms single and multiple MBOX files with MBOX files in Office 365 without any changes in its email formatting, styles, header, etc.
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