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Firefox or Adobe will not allow downloading useable PDF files anymore. Started with last update of Adobe/Firefox.

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For the last few days, I think it was after an update in Firefox or an update in Adobe reader, I cannot save a PDF file from the web and then open it with either Adobe Reader or PDFlite.

The file opens and I can read it just fine within Firefox using Adobe Reader, I guess as a plug in.

But if I save the file as a PDF it saves just fine, with a PDF extension, but when I try to read the PDF file with Adobe or PDFlite it gives an error message - "Adobe Reader could not open <filename> because it is either not a supported file type or because the file has been damaged (for example, it was sent as an email attachment and wasn't correctly decoded)."

I download a lot of datasheets so this is suddenly a major problem for me.

Thanks - Don

For the last few days, I think it was after an update in Firefox or an update in Adobe reader, I cannot save a PDF file from the web and then open it with either Adobe Reader or PDFlite. The file opens and I can read it just fine within Firefox using Adobe Reader, I guess as a plug in. But if I save the file as a PDF it saves just fine, with a PDF extension, but when I try to read the PDF file with Adobe or PDFlite it gives an error message - "Adobe Reader could not open <filename> because it is either not a supported file type or because the file has been damaged (for example, it was sent as an email attachment and wasn't correctly decoded)." I download a lot of datasheets so this is suddenly a major problem for me. Thanks - Don

All Replies (5)

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Firefox 19 introduced a built-in PDF Viewer. It has a very different toolbar from Adobe Acrobat, so you probably would have noticed the change. On the right end of the toolbar there is a download button. Does this sound relevant? To save the PDF from the viewer, you would want to use the download button.

More information on the viewer, and how to change your PDF application handler if you like:

I notice you have both the Adobe PDF plugin and "SumatraPDF". I don't have any experience with the latter. What do you think of it?

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Hi jscher2000,

Okay, I tried the download button and that worked, but now every time I open the file Adobe tells me that it is from an unknown publisher and I have to click that message away to open the file.

Yes, the viewer in Firefox I noticed is now an ugly dark background. And the "Save as PDF" still saves a PDF extension file that appears to be good, but later you find that it is junk and you have to go find the file again.

Why let the "save as PDF" be there if is does not work??

Why can't software people just leave alone things that work!!!!

Is there some advantage in the new method that outweighs all of the negatives?

Don

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Hi Don, there might not be an advantage for you if Adobe works well for you. There are some articles on the motivation for developing a non-proprietary PDF reader -- which is definitely a work-in-progress -- but I don't have the references handy.

Let me tackle some of those individual items:

(1) Unknown publisher warning. This is odd, do you notice that with any other downloads?

It might be a feature of Windows download security. By default, Firefox marks downloads as having come from the internet. You can turn that off by turning off Firefox's antivirus integration. Your real-time AV software still will check files once they are downloaded; this feature is really for people who do not have full-time AV, only on-demand AV.

To toggle that setting:

(i) In a new tab, type or paste about:config in the address bar and press Enter. Click the button promising to be careful. This is Firefox's about:config preferences editor.

(ii) In the filter box, type or paste scan and pause while the list is filtered

(iii) Double-click browser.download.manager.scanWhenDone to switch it from true to false. You're done with about:config.

Does that affect the warning?

(2) Where do you see "Save as PDF"?

I have "Save Page As" on the menu. That worked when I tried a simple PDF. By worked I mean it opened without complaint in Adobe Reader. I suspect it's doing the same thing as the download button.

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Hi Jscher2000,

Yes it was the "Save Page As..." that I was using when it did not work. This did not work for multiple PDF files that I tried. It saved a file with an extension .pdf but the Adobe Reader would not open the file. See previous message I typed in. The "Save File As" is the way I have always saved PDF datasheets for years. I sent one of the bad .pdf datasheet files that I downloaded to a friend and he was not able to open the file either. But when I went back with Firefox to one of the datasheets that I wanted on my computer and used the download button in the top dark window that saved a file that worked. As a hint I also noticed that the file save that did not work in Adobe reader also had resulted in a file folder being saved, a file folder with the same name as the PDF. Inside that folder were several files which I think had an extension .js or something like that. After getting a working PDF downloaded I deleted the non-working PDF file and I deleted the new folder with the PDF file's name.

Once I have downloaded pdf files and saved them on my machine, can I then turn off the flag on that file that says is was Internet sourced? Or is my only option to turn off the function for all downloaded files in advance? Certainly my datasheets that I have had on my machine since before this problem happened (accumulated over many years) do not have the warning message when I open them.

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The folder-full-of-files is created if you save a page using the "Web page, complete" option, which I did not test. Sounds like a bug if that changes how a PDF is saved. Also, I tested in Firefox 20 which I think just released today.

Wait -- stop press -- that was a Firefox 19 bug (#738952) that has been fixed in Firefox 20. You can grab the update when you're ready using

Help menu > About Firefox

As for the internet source attribute, there might be a way to remove it from individual files using a purpose-built utility, but I haven't searched for one.