Unable to open an attachment with Thunderbird

March 2018


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.
Published by deri58. Latest update on May 1, 2010 at 09:37 AM by jak58.
This document, titled "Unable to open an attachment with Thunderbird," is available under the Creative Commons license. Any copy, reuse, or modification of the content should be sufficiently credited to CCM (https://ccm.net/).
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