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Unable to install add-on on my mac

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  • Last reply by TonyE

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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

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