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Cannot open PDF's in new update

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Mac OS snow leopard, firefox 36.01...Since the latest update, my pdf downloads try to open as "cgi" files, and then won't open if i say preview.. I checked "extensions" and have none. i looked at my "preferences / applications / file" is already set to "preview"

my current workaround is to use chrome.

Mac OS snow leopard, firefox 36.01...Since the latest update, my pdf downloads try to open as "cgi" files, and then won't open if i say preview.. I checked "extensions" and have none. i looked at my "preferences / applications / file" is already set to "preview" my current workaround is to use chrome.

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If files get saved with the wrong file extension then you will have to rename them and add the correct file extension, in this case .pdf, yourself to make the file work properly if you double-click the file.

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


Clear the cache and remove cookies only from websites that cause problems.

"Clear the Cache":

  • Firefox > Preferences > Advanced > Network > Cached Web Content: "Clear Now"

"Remove Cookies" from sites causing problems:

  • Firefox > Preferences > Privacy > "Use custom settings for history" > Cookies: "Show Cookies"