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What is the maximum size of attachment for outgoing mails in Thunderbird, unable to send even more than 3MB attachment, however error displaying global size 4MB

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  • Last reply by christ1

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Using Thunderbird (TB) since long but could not identify, why TB is blocking attachment size 3 MB and more however other mail clients don't do this. Even i could able to send, by creating Link of same attachments using TB.

Thanks Shubh

Using Thunderbird (TB) since long but could not identify, why TB is blocking attachment size 3 MB and more however other mail clients don't do this. Even i could able to send, by creating Link of same attachments using TB. Thanks Shubh
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Modified by Shubh

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The limit is imposed by your email provider, so you should talk to them. Binary attachments to an email message are MIME encoded, so there's a significant overhead. In other words, the encoded message with the attachment is bigger than the original file to be attached. https://luxsci.com/blog/raw-vs-encoded-email-message-size-whats-the-difference.html

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christ1 said

The limit is imposed by your email provider, so you should talk to them. Binary attachments to an email message are MIME encoded, so there's a significant overhead. In other words, the encoded message with the attachment is bigger than the original file to be attached. https://luxsci.com/blog/raw-vs-encoded-email-message-size-whats-the-difference.html

@Christ1#I am able to send lager attachments 4MB or even more with another clients i.e Outlook 2016, at same time and same mail-id. So, i suspect how could this limit is imposed by my email service provider.

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Thunderbird has no built-in limit for the attachment size. As said before, you should talk to your email provider.