Forwarded mail contains invisible attachment. How do I see it?
When people forward me an email with an attachment that the original mail contained, I see no attachment in the mail despite it being there if I look in the mail source. Multiple senders, multiple mail programs on the other side (though they mainly use apple mail), Thunderbird on mine, same problem everywhere. If they download the attachment and add it themselves it works fine, but that is no solution. That's a workaround that I can't expect everyone I work with to do. Is there an easy fix or an add-on that I haven't found that can fix this?
Chosen solution
here is my suggestion.
Save the email as an eml file to your desktop edit it in notepad or another plain text editor. Change the Content-Disposition: inline; ot Content-Disposition: attachment;
Save the email and open in Thunderbird by double clicking. I have no idea why a PDF would be declared as inline, but it aint going to happen in any mail client I know about. But apple might have inline for PDF in their mail clients.
If that works, you should be able to view the attachments in all mail simply by changing the hidden preference in the config editorfor mailnews.display.html_as to 4.
Allowable values are 0 (default): Display the HTML normally 1: Convert it to text and then back again 2: Display the HTML source 3: Sanitize the HTML 4: Display all body parts
This will see you have lots and lots more attachments, as all inline images from say signatures with images in them will appear as attachments. Butit will d these apparently mis coded attachments.
What I am not sure of from what you have said if at what point they become inline instead of attachments. I would like to know if it is happening as a Thunderbird bug or a bug in the sending software.
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when you look in the message source how is the attachment defined?
In the latest test it was apple mail:
--Apple-Mail=_C27BE278-F153-4DD3-A9AD-5175F2825627 Content-Disposition: inline; filename=91801-digium.pdf Content-Type: application/pdf; x-unix-mode=0644; name="91801-digium.pdf" Content-Transfer-Encoding: base64
And then a lot of gibberish thats the attached pdf. Thats from the source of the forwarded email. It looks exactly the same in the directly sent email, in which the attachment can be accessed. The only difference here seems that in the forwarded email it's a lot of html, which isn't there in the newly made email, before the attachment. The html code seems to be about the blue bar that appears to the left of the previous emails text.
I wonder if it's the html that stops Thunderbird from reading attachments that's added after. I'll have to conduct some strange test there I think.
Modified by Arystair
Chosen Solution
here is my suggestion.
Save the email as an eml file to your desktop edit it in notepad or another plain text editor. Change the Content-Disposition: inline; ot Content-Disposition: attachment;
Save the email and open in Thunderbird by double clicking. I have no idea why a PDF would be declared as inline, but it aint going to happen in any mail client I know about. But apple might have inline for PDF in their mail clients.
If that works, you should be able to view the attachments in all mail simply by changing the hidden preference in the config editorfor mailnews.display.html_as to 4.
Allowable values are 0 (default): Display the HTML normally 1: Convert it to text and then back again 2: Display the HTML source 3: Sanitize the HTML 4: Display all body parts
This will see you have lots and lots more attachments, as all inline images from say signatures with images in them will appear as attachments. Butit will d these apparently mis coded attachments.
What I am not sure of from what you have said if at what point they become inline instead of attachments. I would like to know if it is happening as a Thunderbird bug or a bug in the sending software.
That actually pointed me in the right direction. It turns out it was set to 1 for some reason I dont know and mailnews.display.prefer_plaintext was set to true (default is false). Changing both of those back to default actually fixed the issue. Thank you for the quick help Matt! You're a diamond!