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Ad Block Plus will not install. "Firefox could not install the file." What can I do?

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

Beaufortc
Beaufortc
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Error message is Firefox could not install the file at

https://addons.mozilla.org/firefox/downloads/latest/1865/addon-1865-latest.xpi?src=addondetail

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

Error message is Firefox could not install the file at https://addons.mozilla.org/firefox/downloads/latest/1865/addon-1865-latest.xpi?src=addondetail because: Unexpected installation error Review the Error Console log for more details. -203

All Replies (1)

TonyE
TonyE
  • Moderator
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This link should help - https://support.mozilla.com/kb/Unexpected+installation+error+-203+when+installing+add-ons