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Firefox has changed all my Adobe PDFs to Firefox HTML Documents!

  • 3 replies
  • 32 have this problem
  • Last reply by pmkap

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I was having trouble opening up new pdfs -- Firefox would start opening up multiple tabs until I closed firefox -- and then I realized that (a) it did the same for opening existing pdfs, and (b) it had changed the file type on all my existing pdfs to Firefox HTML documents. Quite disturbing. Adobe Acrobat and Firefox are both up-to-date...what can I do to restore proper settings?

All Replies (3)

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You can rename (or delete) the mimeTypes.rdf file in the Firefox profile folder to reset all file actions.

You can use this button to go to the currently used Firefox profile folder:

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Way beyond my technical abilities. How/why did Firefox suddenly make these changes, and isn't there any easy way to undo?

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Your suggestions didn't work. But the solution to this problem is found -

The chosen solution works. All you need to do is apply (in my case in windows explorer on an acient XP machine) it to one pdf file that has been changed to a firefox html file, and it will change ALL the corrupted PDF files back to PDFs. It will leave those files that actually are HTML files alone. FWIW