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Firefox does not open Acrobat after downloading a file

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Although Acrobat is properly installed as an application in Firefox, each time Firefox downloads a PDF file, instead of opening the file, I get a pop up box asking me whether or not to open the file.

The box labeled 'Do this Automatically' is blocked out.

What am I missing???? How do I fix this?????

Although Acrobat is properly installed as an application in Firefox, each time Firefox downloads a PDF file, instead of opening the file, I get a pop up box asking me whether or not to open the file. The box labeled 'Do this Automatically' is blocked out. What am I missing???? How do I fix this?????

All Replies (5)

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This does not solve my problem. Please see the image capture.

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Hi Wmbiird, the problem is that the server is sending a non-specific content type. Instead of specifying application/pdf it is sending application/octet-stream which is a generic content type that Firefox won't associate with a standard action, even if you tell it to do so.

(See attached screenshot.)

You might wonder why the site is using a non-specific content type when every webmaster knows how to identify a PDF, and the most likely explanation is that the site wants to force a download dialog, bypassing the behavior of showing a PDF in a tab.

Edit: There's a discussion of this content type here: https://developer.mozilla.org/docs/Web/HTTP/Basics_of_HTTP/MIME_types#Important_MIME_types_for_Web_developers

jscher2000 - Support Volunteer trɔe

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jscher2000:

Thanks for your reply. I read the link and the attachment and the explanation is above my pay grade. Why there is this difference is totally beyond me. As Firefox recognizes the file is a PDF, why should the response be different?

I initiated the download by clicking on a link.

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If you're asking why Firefox doesn't just disregard the unhelpful content-type information and base its behavior on the file extension, I don't know the original reasoning, but it has always been that way. In another thread today, the server was sending a .png image file with the content type text/plain, so Firefox suggested opening it in Notepad. Webmasters are supposed to do things right.