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Unable to install add-on on my mac

  • 1 reply
  • 6 have this problem
  • 5 views
  • Last reply by TonyE

lcarper
lcarper
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I am unable to install any add-on to my Mac. The message I receive is:

Firefox could not install the file at

https://addons.mozilla.org/en-US/firefox/downloads/latest/4076/addon-4076-latest.xpi?src=external-AT_tooldl

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

I am unable to install any add-on to my Mac. The message I receive is: Firefox could not install the file at https://addons.mozilla.org/en-US/firefox/downloads/latest/4076/addon-4076-latest.xpi?src=external-AT_tooldl because: Unexpected installation error Review the Error Console log for more details. -203

All Replies (1)

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