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Large attachments stop sending and require intervention.

  • 3 replies
  • 1 has this problem
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  • Last reply by sfhowes

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I call Thunderbird from a program to send out emails in batches. When an attachment exceeds approximately 14 MB, Thunderbird stops sending and requires manual intervention. The messages become stacked in a queue. I then must click the "Write" button for each message. I've modified the config file per a previous suggestion which makes a warning dialog disappear. However, Thunderbird still won't automatically send messages with attachments beyond approximately 14 MB. Is there a way to circumvent this behavior?

I call Thunderbird from a program to send out emails in batches. When an attachment exceeds approximately 14 MB, Thunderbird stops sending and requires manual intervention. The messages become stacked in a queue. I then must click the "Write" button for each message. I've modified the config file per a previous suggestion which makes a warning dialog disappear. However, Thunderbird still won't automatically send messages with attachments beyond approximately 14 MB. Is there a way to circumvent this behavior?

All Replies (3)

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Are you sure your service provider allows messages larger than 20MB? Keep in mind that encoding overhead adds about 33% to the size of an attachment, so a 15MB file results in a message of about 20MB.

The most efficient way, for both sender and recipient, to send large files is to upload the file to a (free) hosting service like OneDrive, Google Drive, Dropbox etc. and send the download link by email.

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Thanks for the reply... Yes, the service provider allows the attachments since when the messages become stacked, (Send windows), I simply click each send window's "Send" button and off the message goes.

I think I will try introducing a larger delay factor between sending messages. Right now I wait 30 seconds between each message. I'm just wondering if I am overwhelming TBird even though each message receives its own thread.

Thanks again...I'll report back

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If the problem is due to too many 'sends in the stack', it may work better if you Send in the Background:

http://kb.mozillazine.org/Thunderbird_3.0_-_New_Features_and_Changes#Send_in_Background