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error application has failed to start because plds4.dll keeps popping up - how do I fix it?

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I'm trying to open Firefox & this error keeps popping up:

"error application has failed to start because plds4.dll"

I've tried reboot the computer but that has not helped.

I'm trying to open Firefox & this error keeps popping up: "error application has failed to start because plds4.dll" I've tried reboot the computer but that has not helped.

All Replies (2)

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hello darcyK, please try to reinstall firefox:

  • download the full firefox setup file from getfirefox.com
  • uninstall firefox on the machine (but don't chose to delete your custom files & settings in the uninstaller)
  • manually delete all remaining files in the firefox program folder, which usually resides in C:\Program Files\Mozilla Firefox\
  • reinstall firefox
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You can also try to run Firefox once as Administrator or reboot the computer and login as Administrator to see if that helps.