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Firefox thinks .swf files are "application/x-shockw" instead of "application/x-shockwave-flash" and thus won't play them.

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Hey, so I've been trying to get a few .swf files on my computer to play properly in Firefox, but they refuse to work. Instead of the "application/x-shockwave-flash" that they are supposed to be (which should play properly according to my Options -> Applications tab), they seem to be registering as "application/x-shockw", which (according to my Options -> Applications tab), will ask me what to do (giving me the option to "open" or "save" (opening it just opens a new tab which then gives me the option to "open" or "save", etc). I tried setting the default action on these files to use the flash player plugin but it won't let me select it, it's not appearing in the list.

Hey, so I've been trying to get a few .swf files on my computer to play properly in Firefox, but they refuse to work. Instead of the "application/x-shockwave-flash" that they are supposed to be (which should play properly according to my Options -> Applications tab), they seem to be registering as "application/x-shockw", which (according to my Options -> Applications tab), will ask me what to do (giving me the option to "open" or "save" (opening it just opens a new tab which then gives me the option to "open" or "save", etc). I tried setting the default action on these files to use the flash player plugin but it won't let me select it, it's not appearing in the list.

All Replies (3)

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It sounds as though the settings file which stores those download handling preferences is corrupted. Because its internal structure is somewhat inscrutable, the standard medicine is to remove it and have Firefox rebuild it. Here's how:

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

  • "3-bar" menu button > "?" button > Troubleshooting Information
  • Help menu > Troubleshooting Information

In the first table on the page, click the "Show Folder" button

Leaving that window open, switch back to Firefox and Exit, either:

  • "3-bar" menu button > "power" button
  • File menu > Exit

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

In case the plugin database is messed up, you also could rename pluginreg.dat to pluginreg.old.

Start Firefox back up again. Any improvement?

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Yes! Thank you so much, this was a ridiculously easy fix and apparently a relatively easy to identify problem, I'm surprised I couldn't find a solution anywhere. Thank you so much for the help, that appears to have fixed it!

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Thank you for updating us, and hopefully it won't happen again.