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WesDIC's avatar
WesDIC
Copper Contributor
Apr 11, 2024

How do I export Thunderbird inbox mail into my Microsoft Exchange Server Inbox?

We have been trying to find good email client applications that have a unified inbox and do certain things we prefer. Upon doing so we used Thunderbird which by default for POP accounts it has the "Delete Messages after 14 days" selected... we did not realize this and have lost years worth of emails off of our Microsoft Exchange servers due to this issue. Thunderbird still has ALL of our emails... The size of emails and profile is about about 98gb... which is higher than Thunderbirds normal 2gb export. 

 

How do I export all of these inbox emails out of Thunderbird to then somehow import them back into our Microsoft Exchange server inboxes so they repopulate again for IMAP users? One article I read said the Import to Microsoft needed to be a CSV file but thunderbird does not export to CSV. Anyone else go through this issue and have a solution? It's extremely disruptive for a few our upper management that this has effected and we need to find a fix to restore all of the emails to the server that Thunderbird settings removed from it's POP settings.

  • harryjung360's avatar
    harryjung360
    Copper Contributor
    Aug 21, 2024

     

    To export Thunderbird emails back to Microsoft Exchange Server, use Thunderbird's "ImportExportTools NG" add-on to export the emails as .eml files. Once exported, use a tool like "MFCMAPI" to import the .eml files into your Exchange inbox. This method avoids the size limit and restores emails for IMAP access.

    To export Thunderbird mailbox to Microsoft Exchange Server inbox, first, use the "ImportExportTools NG" add-on in Thunderbird to export the mailbox as an MBOX file. Then, use a third-party tool like "MBOX Converter" to convert the MBOX file to PST format. Finally, import the PST file into Microsoft Exchange using Outlook’s Import feature or PowerShell. This process allows you to restore the mailbox content back to Exchange for IMAP access.

  • laurencemontgomery's avatar
    laurencemontgomery
    Copper Contributor
    Aug 26, 2024

    Due to various protocols & file formats, exporting Thunderbird inbox emails to Microsoft Exchange Server requires many steps. This task's specific steps are here:

    Step 1: Thunderbird Email Export

    • Add ImportExportTools NG:
    • Launch Thunderbird.
    • Select Add-ons and Themes from the menu.
    • Install ImportExportTools NG from search.
    • Restart Thunderbird.

    Export Inbox:

    • Right-click Thunderbird's Inbox.
    • In ImportExportTools NG, select the Export folder.
    • Choose EML or MBOX for export. For large email transfers, MBOX is best.
    • Save the file: Decide where to store exported emails.

    Second: Import emails to Exchange.

    • For EML, use Outlook.
    • Import EML Outlook:
    • Create an Outlook Exchange Server mailbox.
    • Just place EML files into this folder.
    • Post to Exchange.

    Second Choice: Third-Party Tool

    Convert MBOX to PST:

    Convert MBOX to PST MBOX to PST converter.

    Outlook PST Import:

    • Go to Outlook.
    • File > Open/Export > Import/Export.
    • Import from another software or file, choose Outlook Data File (.pst).
    • Select the Exchange mailbox folder to import your PST file.

    Exchange Sync:

    After email import, Outlook syncs with Exchange instantly.

    Step 3: Import Review

    • Check your Outlook or Outlook Web Access Exchange Server inbox to ensure all emails were imported.

    Notes: Please backup Thunderbird emails before proceeding.

    Many third-party tools can convert MBOX to PST, especially BLR MBOX Converter. 

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