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In am unable to install pluggins, updates or a toolbar I get an error message each time.

  • 1 reply
  • 1 has this problem
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  • Last reply by TonyE

thomasm74
thomasm74
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I get this error message: "Firefox could not install the file at http://releases.mozilla.org/pub/mozilla.org/addons/1122/tab_mix_plus-0.3.8.4-fx.xpi

because: Unexpected installation error..."

I get this error message: "Firefox could not install the file at http://releases.mozilla.org/pub/mozilla.org/addons/1122/tab_mix_plus-0.3.8.4-fx.xpi because: Unexpected installation error..."

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TonyE
TonyE
  • Moderator
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For details on fixing that error see https://support.mozilla.com/kb/Unexpected+installation+error+-203+when+installing+add-ons