Could you describe this problem in a little more detail: are you saving the file, and they end up saved with a .pdf extension, or instead of saving them, Firefox loads them in the PDF viewer??

Normally, Firefox can't actually convert a Word document to a PDF, but maybe an add-on could do that. Can you think of any add-ons you installed that might have that feature?

Sometimes the file that stores your download action preferences gets corrupted. You can rename the file and re-train Firefox on how to handle different types of files. Here's how:

Open your current Firefox settings (AKA Firefox profile) folder using

Help > Troubleshooting Information > "Show Folder" button

Switch back to Firefox and Exit

Pause while Firefox finishes its cleanup, then rename mimeTypes.rdf to something like mimeTypes.old

Restart Firefox and test Dropbox again. Hopefully now it will work normally.

More detail: I save my Word files as Microsoft Word documents in my Dropbox folder. Whenever I view them in my browser (Firefox or Chrome) on the Dropbox site they are visible as 'document docx'.

When I click on the document in Chrome, it opens as a normal Word file, but in Firefox it opens it as a PDF.

I uninstalled Firefox and removed all related extensions & plug-ins. I then installed the latest version of Firefox and I'm having the same problem.

I followed your advice above "Opened my current Firefox settings (AKA Firefox profile) folder using Help > Troubleshooting Information > "Show Folder" button Then I switched back to Firefox and hit exit.

I paused for a minute while Firefox finished its cleanup, then renamed mimeTypes.rdf to "mimeTypes.old"

I then reopened Dropbox in Firefox and had the same problem.

I've attached 2 screenshots to give you an idea of what I'm seeing.

That's baffling. Where is Firefox getting that from?

In my old profile (years of accumulated settings), on a system with Word 2010, Dropbox works normally. I have to test in a fresh profile to see whether it also picks up the settings correctly -- but I can't close Firefox right now...

Do you notice problems opening Word documents from other sites? You can use these results to test:

• site:microsoft.com filetype:doc - Google Search
• site:microsoft.com filetype:docx - Google Search

I reset the settings in Firefox to default but the problem persists.

Firefox downloads Word files from other websites without any difficulty.

Normally, Firefox should behave consistently when sites send the same content-type header, in the case of a .doc, typically application/msword. It's very puzzling that your Dropbox downloads behave differently.

If you go back out to your profile folder and open mimeTypes.rdf in a text editor and search for msword, do you see it associated with anything other than Microsoft Word?

Edit: By the way, the screen shots are generated as follows. Go to the page with the link. Open the web console using Ctrl+Shift+k. Click the link. Cancel the Open/Save dialog. Then click the request in the web console to view the response headers.

I opened mimeTypes.rdf in notepad and didn't find anything related to 'msword' or even just 'word'

I followed your directions on the screenshot and have attached a screenshot of what I got

Hi Bryan, on the last screenshot, try clicking the line which has the URL is on dl-web.dropbox.com, then scroll the box down to the bottom where the Response Headers are listed. I'm expecting you'll see the Content Type is application/msword but if it's something else, that would be a clue.

Your suspicions were right. Under content type it says 'application/pdf'

I think that might be right in that case -- it actually is a PDF file, at least judging by the appearance of the built-in Firefox PDF viewer in the background.

What about the "CBDA Project.doc" from your earlier screen shot. Does that one show application/pdf even though Dropbox shows a document icon?

Okay, so I was going through the steps in the CBDA folder and noticed that there are some Word Files which are marked as 'doc' and others that are 'docx.' (See first screenshot) I don't know how they were saved differently, but they are all Word files. When I click the docx files, Firefox reads them as Word files. When I click doc files, Firefox reads them as PDFs. I've attached screenshots of each type of file being opened and the info that I got with each action.

On the DOC, it's weird, at the end of the URL highlighted in the web console it says convert_doc_to_pdf=1. I don't know where that is coming from, but that probably needs to go.

On the DOCX, if text/plain works for you, that's great, but the expected type is this absurdly long string: application/vnd.openxmlformats-officedocument.wordprocessingml.document

Really not sure what is causing these changes. Does Firefox connect through a filter or proxy different from your other browsers? This usually would be set here:

orange Firefox button (or Tools menu) > Options > Advanced > Network "mini-tab" > "Settings" button

Forgot to mention: DOCX is the default format in Word 2007 and later, but some users/companies stick to the earlier DOC format for maximum compatibility. If the files were developed collaboratively with others, this could explain how you ended up with a mix of formats.

Here are the proxy settings.

Man, you work a long day: I really appreciate this!

"Use system proxy settings" should cause Firefox to follow your IE settings, so if IE works, that can't be it.

When you said you reset Firefox to default settings, did you reinstall any extensions after that before testing? You can review your extensions for any potential culprits here:

orange Firefox button (or Tools menu) > Add-ons > Extensions category

Nope, didn't reinstall any extensions. I disabled Norton to see if it made any difference but it didn't.

I think I see now. Dropbox may push the download directly from the small pop-up, which should always give you a DOC, and may give you a preview featuring Firefox's native PDF viewer. On the preview, you need to use the button the blue frame to get the native format, otherwise you get the converted-to-PDF download. I hadn't noticed this preview before until I used the share button for this document. Now I get the preview window for that document like you do. Apologies for not being aware of how to trigger this much earlier in the discussion.

AH! So the blue bar download button opens it up in the original format!? Wow - I feel so silly! I really thought it would be all the same! Thanks so much for all your time and help! It's been educational! Much obliged!

THANK YOU for posting the original question and the answer. I'd just started running into this myself this week and it made me batty.

An alternate solution: highlight the doc file you want to download by clicking on any information in the rightmost columns (file type or date, e.g.), and then use the download command/icon in the light blue bar at the top of your file list. This bypasses the whole preview/PDF step entirely.

However, it's still less efficient and a lot less intuitive than just clicking on the dang doc name and having it automatically download, as it used to do.

To the original poster, should you ever return: I don't think you're silly. You're assuming that your DOC is a DOC just as it has always been when you've downloaded a thousand docs before from Dropbox via Firefox.

To Firefox programmers: REALLY?? Surely there has to be a way to launch a preview of a DOC, if that's so necessary, without making it a 50/50 chance that the user will download it in a surprise format. (Pick a download icon, black or blue.) Do we need the PDF option at all? Is there really anyone out there who wants their very own personally created Dropbox DOCs downloaded as PDFs? anyone? anyone? Bueller?