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I am having a problem installing Grease Monkey

  • 1 reply
  • 45 have this problem
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  • Last reply by TonyE

indianachris
indianachris
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Getting error:

Firefox could not install the file at

https://addons.mozilla.org/en-US/firefox/downloads/latest/748/addon-748-latest.xpi?src=search

because: Unexpected installation error Review the Error Console log for more details. -203

Getting error: Firefox could not install the file at https://addons.mozilla.org/en-US/firefox/downloads/latest/748/addon-748-latest.xpi?src=search because: Unexpected installation error Review the Error Console log for more details. -203

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TonyE
TonyE
  • Moderator
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See Unexpected installation error -203 when installing add-ons