Unable to open an attachment with Thunderbird

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When trying to open an attachment with Thunderbird, below error message appears on your screen:
[Thunderbird] error message:  
"Unable to save the attachment. Please check the filename and try again." 

This is due to a forwarded message that itself contain an attachment which however generates a bug under thunderbird. This is actually being worked by Thunderbird team which will be corrected for the future version.


  • Below is a temporary proposed solution
  • Click on View and then View attachments in messages .

Alternative solution

  • If the first does not work, or if there are more than two messages, you can save the file on your hard disk.
  • Then right click on the file and click on Save as >OK
  • Then open the file from your desktop.
  • Open the attachment by double clicking on it.

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