After download google mail via takeout. The files download is .zip format. You can read your email message by free mail client (Thunderbird).

Pre-request
  1. Thunderbird program (Donwload link).
  2. Data files .zip (Archive mail from google via takeout).
Step1: Install Mozilla Thunderbird

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Step2: Open mbox file on Mozilla Thunderbird

  1. Open Mozilla Thunderbird

  2. Welcome page, Select i'll configure my account later.
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  3. Brows folder (C:\Users\YourUser\AppData\Roaming\Thunderbird\Profiles*.default\Mail\Local Folders)
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  4. Open file .zip from download
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  5. Copy file .mbox to folder (C:\Users\YourUser\AppData\Roaming\Thunderbird\Profiles*.default\Mail\Local Folders)
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  6. When copy finish. Go back to Mozilla Thunderbird windows (It'll not show update until restart program.
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  7. Close and reopen Mozilla Thunderbird program.
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  8. Folder will show on list "All mail Including".

  9. Click on folder to check message inside.
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  10. Attached file also include inside message.
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  11. All done.