Are you switch the Outlook PST files into Thunderbird Account. I recommended the Softaken PST to MBOX Converter Tool is fast solution to switch the Outlook PST files into Thunderbird .mbox file format. This tool supports all email clients of the MBOX file such as Apple Mail, Power Mail, Thunderbird, Eudora, etc. You can easily to convert one and multiple PST files into MBOX file format. It allows to convert all emails from PST files into MBOX file format. It supports all Windows OS versions.

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