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How come I can not longer add an attachment to an outgoing email in Thunderbird?

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It's very strange. I have used Thunderbird for years and just today I tried to add an attachment to an email, like I have done thousands of times before and now when I click on add attachment nothing happens. What do I do?

It's very strange. I have used Thunderbird for years and just today I tried to add an attachment to an email, like I have done thousands of times before and now when I click on add attachment nothing happens. What do I do?

All Replies (4)

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Hello there Bob136 We have read your message We try to help you.


https://support.mozilla.org/en-US/kb/how-use-attachments


Can’t and cannot send emails


Option 1 : Verify that the Correct SMTP Setting is Being Used

Again, launch the Thunderbird application to fix Thunderbird won’t send email. Then, go to Tools>>Account Settings. Or, click on the three bars on the top-right hand side and go to Options>> Account Settings. From the Account Settings dialogue box, select the account name having Thunderbird email problems sending.

Next, verify that the correct SMTP server is being used for the email address. For example, email cannot be sent via abc@gmail.com through Yahoo SMTP.


Option 2 : Check the SMTP Settings

First, launch the Thunderbird application to remove Thunderbird email problems sending when Thunderbird inbox is full. Then, go to Tools>>Account Settings. Or, click on the three bars on the top-right hand side and go to Options>> Account Settings. From the Account Settings dialogue box, select Outgoing Server(SMTP).Then, check to make sure that the SMTP settings are correct for the email account configured.

Next, click on Edit button to change SMTP details and remove Thunderbird email problems. Also, go to the email provider’s website and search for Mail Settings>>SMTP. Then, verify that the Thunderbird settings match the documented settings







Greetings Firefox Volunteer.

Modified by День сумо

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Hello there Again



Option 1:Try to Repair Folder


To open the Thunderbird attachments in a trouble-free way one can try to repair folder in which the specific email to which the attachment is associated is present

1. First of all, open Thunderbird and select the folder in which the email is present to which the attachment is associated

2. After that, right-click on the folder and select Properties option

3. In the Folder Properties windows, you will see the Repair Folder button. Click on the Repair Folder button and then click on OK

4. Once the repair process is completed, the issues related to email, header, attachment etc. will be resolved

5. Now, try to open the attachment again





Greetings Firefox Volunteer.

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Does it work in safe mode? Hold Option when you launch TB, or Help/Restart with add-ons disabled.

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Hello there Bob136.

just an answer to the situation right now is that it could be that traffic on the internet (Stmp server)could hinder this option? for example, are small messages successful with a large attachment? Or could it not work the other way around?

It is also possible that your antivirus program software has a certain mode for outgoing traffic switched off in this case outgoing mail.


try looking it up and message us back immediately.

for more answers to help you.


Greetings Firefox Volunteer

Modified by День сумо