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Forwarded attachments are corrupted or deleted

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I am running Thunderbird 38.3.0 on Windows 7. When forwarding a mail with attachments the attachments become either corrupted or deleted. I have not been able to find any logic behind this, as sometimes it happens and sometimes it doesn't. What I have found is as follows: 1) Sometimes, when forwarding a mail with an attachment, I check the attachment before pressing "send" and I get the message which you will see in the screenshot I have attached (the 2nd attachment). The person receiving the mail also cannot open the attachment. 2) When forwarding a mail with a number of attachments in different formats, only one format will be forwarded. In other words, if there are 2 PDF documents and 2 Word documents and a JPG image. it will either send only the PDF or only the Word or only the JPG. The other documents just do not appear in the forwarded message and seem to have vanished into thin air! Sometimes when this happens, part of one of the pages that is forwarded is only partly visible. (see 1st attachment).

I read all the other comments on this in the forum and no one seems to have any idea how to solve it. I have tried everything that was suggested and nothing seems to change this.

The way I deal with this is that every time I forward a message with attachments I check the attachments before sending to make sure they are really there and not corrupted. If there is a problem, I save the attachments from the original mail on my PC and then attach them manually to the mail I am sending. This works OK but is a real pain in the backside!

If any more information is required, let me know.

Eric

I am running Thunderbird 38.3.0 on Windows 7. When forwarding a mail with attachments the attachments become either corrupted or deleted. I have not been able to find any logic behind this, as sometimes it happens and sometimes it doesn't. What I have found is as follows: 1) Sometimes, when forwarding a mail with an attachment, I check the attachment before pressing "send" and I get the message which you will see in the screenshot I have attached (the 2nd attachment). The person receiving the mail also cannot open the attachment. 2) When forwarding a mail with a number of attachments in different formats, only one format will be forwarded. In other words, if there are 2 PDF documents and 2 Word documents and a JPG image. it will either send only the PDF or only the Word or only the JPG. The other documents just do not appear in the forwarded message and seem to have vanished into thin air! Sometimes when this happens, part of one of the pages that is forwarded is only partly visible. (see 1st attachment). I read all the other comments on this in the forum and no one seems to have any idea how to solve it. I have tried everything that was suggested and nothing seems to change this. The way I deal with this is that every time I forward a message with attachments I check the attachments before sending to make sure they are really there and not corrupted. If there is a problem, I save the attachments from the original mail on my PC and then attach them manually to the mail I am sending. This works OK but is a real pain in the backside! If any more information is required, let me know. Eric
Attached screenshots

Endret av thunderbird151

All Replies (8)

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I have just found a further problem. I tried to forward a mail with 3 attachments of the same type (PDF). Only one of them appeared in the forwarded mail, and it was corrupt. The other 2.......yes you guessed it....disappeared! This is getting to be very troubling, Sometimes I forward mails and forget to check the attachments and people just don't receive what I send them. There must be a solution to this mess somewhere. HELP !!!

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We have multiple issues here I think.

1. Many attachments are attached by programs that do it outside the FRC standard for mail. Thunderbird will display these defective emails, but forwarding them will see the attachments disappear. Web mail and scripts of web sites and devices sending logs are really bad for defective mime encoding.

2. You finding the file locked points to an external source such as an anti virus scanning the file before transmission. Disable any sort of attachment scanning for outgoing mail. It is pointless, the product doing the scanning has already said you have not got a virus. They do not spontaneously appear.

As a test you could try restarting the operating system in safe mode with Networking'. This loads only the very basics needed to start your computer while enabling an Internet connection. Click on your operating system for instructions on how to start in safe mode: Windows 8, Windows 7, Windows Vista, Windows XP, OSX

If safe mode for the operating system fixes the issue, there's other software in your computer that's causing problems. Possibilities include but not limited to: AV scanning, virus/malware, background downloads such as program updates.
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In answer to the last comments: 1) I don't understand why only Thunderbird has problems with attachments. All other mail programs seem to handle attachments with no problem, no matter where they come from ! 2)My anti virus is set to not check outgoing e-mails 3) Safe mode with networking didn't change anything

I also found that even when I have a number of attachments in the same format, it only forwards some of them (usually only 2)

This is driving me crazy!

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thunderbird151 said

In answer to the last comments: 1) I don't understand why only Thunderbird has problems with attachments. All other mail programs seem to handle attachments with no problem, no matter where they come from !

Thunderbird also does not tell you to not open attachments or suffer from most of the security issues that those programs which accept poorly formatted attachments do. It is just that Thunderbird is strictly RFC compliant. Other not so much. I can not help it is most web programmers have no idea how to correctly compose an email, and most of the JavaScript libraries they use require at least a passing familiarity with the standards.

2)My anti virus is set to not check outgoing e-mails

So what process do you think is locking the file so Thunderbird can not get access to it?

3) Safe mode with networking didn't change anything

That is unfortunate.

I also found that even when I have a number of attachments in the same format, it only forwards some of them (usually only 2)

View the message source (ctrl+U) How is the attachment described in the message source?

For example a Zip file would look like this

Content-Type: application/x-zip-compressed;
name="Emails.zip"
Content-Transfer-Encoding: base64
Content-Disposition: attachment;
filename="Emails.zip"
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I tried turning off my anti-virus but that didn't change anything. As an example of my problem, I received an e-mail with 2 JPG files attached, which opened fine on arrival. When I forward the mail only the first attachment appears and when I try to open it I only see half of the picture and the other half is grey. I went to the message source and the attachments are described as follows:

1) Content-Type: image/jpeg; name="IMG_6259.jpg" Content-Description: IMG_6259.jpg Content-Disposition: attachment; filename="IMG_6259.jpg"; size=1876016; creation-date="Tue, 10 Nov 2015 22:45:15 GMT"; modification-date="Tue, 10 Nov 2015 22:46:21 GMT" Content-Transfer-Encoding: base64

2)Content-Type: image/jpeg; name="IMG_6262.jpg" Content-Description: IMG_6262.jpg Content-Disposition: attachment; filename="IMG_6262.jpg"; size=1826315; creation-date="Tue, 10 Nov 2015 22:45:21 GMT"; modification-date="Tue, 10 Nov 2015 22:47:21 GMT" Content-Transfer-Encoding: base64

You asked me what process I think is blocking the attachments, but I haven't the faintest idea. If safe mode doesn't help and not operating the anti virus doesn't help, I am at a loss.

By the way, it's all very well to say that other mail programmes don't cover security issues like Thunderbird, but that's what anti virus software is for. If the mail software doesn't do its' job, then it's a waste of time

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Eureka!!!! I found the problem with forwarding attachments. Surprisingly, the culprit is a Thunderbird add-on - "Close On Reply" version 1.1. I tried disabling all add-ons and then enabling one at a time and found that when this add-on is enabled I have the attachment problem, where it either corrupts attachments or sometimes when there are multiple attachment some of them disappear. Is there a newer version of this add-on, or another add-on that does the same job of closing an open window when a reply has been sent?

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The web page for the add-on indicates it has not been updated for V31 or 38. It is a wonder it worked at all.

https://addons.mozilla.org/en-us/thunderbird/addon/close-on-reply/

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Is there any other option to close a message after a reply has been sent?