Tools, Preferences, Files and Attachments

So you clicked on the Content type for JPG - 'Action' to see drop down and selected 'Delete Action' to remove it from list.

Select email

• Right click on jpg attachment and select 'Open'
• What should Thunderbird do with this file?
• Select 'Open with' and choose suitable program - I selected 'Photos (default)'
• Select checkbox 'Do this automatically for files like this from now on'
• click on 'OK'

Thanks for the reply. I did what you suggested but it made no difference - I still get the same error message. So I now uninstalled Mozilla and then downloaded it again and tried once again to open a jpg file attached to an email and again I get the same error message - file " could not be opened, because the associated helper application does not exist. Change the association in your preferences." Once again, I went into Preferences, Files and Attachments and changed all the options on jpg and jpeg to Photos but again this did not solve my problem. Any more ideas please? Thanks Ron

Does the Photos app work normally to open a *.jpg image stored on computer ?

Check: Is 'Photos' set up as a default app on computer ? in windows search type: default select 'Default apps' For 'Photo viewer' select 'Photos'

scroll down and click on 'Choose default applications by file type' Scroll down to .jpeg and .jpg and make sure both have 'Photos' set up as the app to use.

Let's see if the email has malformed mime types.

What do you see in the Source view of email ? Select email so it is visible in Message Pane In the header area, click on 'More' and select 'View Source'

It opens in a new window. check the following types of lines and tell me what you have got in the email.

As an example I have this: Headers ending with: FROM: X To: ME MIME-Version: 1.0 Content-Type: multipart/mixed; boundary="_9DDF9E94-0B3B-9A4B-93A5-4EA0912C8D7F_"

--_9DDF9E94-0B3B-9A4B-93A5-4EA0912C8D7F_ Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset="utf-8"

Some html text content

--_9DDF9E94-0B3B-9A4B-93A5-4EA0912C8D7F_ Content-Type: image/jpeg; name="IMG_20220117_164913_585.jpg" Content-Transfer-Encoding: base64 Content-Disposition: attachment; filename="IMG_20220117_164913_585.jpg"

Followed by a load of jibber jabber of letters and numbers.