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pdf could not be opened, because the associated helper application does not exist. Change the association in your preferences.

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  • Last reply by Toad-Hall

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error message when trying to view attachment in draft email

'pdf could not be opened, because the associated helper application does not exist. Change the association in your preferences.'

error message when trying to view attachment in draft email ''''pdf could not be opened, because the associated helper application does not exist. Change the association in your preferences.''''

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Menu app icon > 'Preferences' > 'General' 'Files & Attachments' section Content Type: HTML Document - What is set up as the Action ? Content Type : PDF - What is set up as the Action ?

Try setting the following, restart Thunderbird and report on what occurs. Content Type: "HTML Document" Action is usually a browser - "Use Firefox Web Browser (default)", changed it to "Always Ask" Content type: "Portable Document Format (PDF)" set Action : "Preview in Thunderbird"

Modified by Toad-Hall