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tried installing ublock, oldest version, got an error message: could not install the file at https://addons.cdn.mozilla.net/user-media/addons/576580/block-0.

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  • Last reply by James

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All attempts to install any add-ons from the Mozilla add-on page resulted in the same message: Firefox could not install the file at

https://addons.mozilla.org/firefox/downloads/file/400263/foxyproxy_standard-4.5.6-fx+sm+tb.xpi?src=api

because: Signing could not be verified. -260 What's this signing thing and why can't I download any add-ons???

All attempts to install any add-ons from the Mozilla add-on page resulted in the same message: Firefox could not install the file at https://addons.mozilla.org/firefox/downloads/file/400263/foxyproxy_standard-4.5.6-fx+sm+tb.xpi?src=api because: Signing could not be verified. -260 What's this signing thing and why can't I download any add-ons???

All Replies (5)

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You've got (out-of-the-Ark) Fx 3.6.28; I've got Firefox 44.0.2. I think this will explain nearly all of your problems. Someone else will give you the best advice on how to start again with Firefox for your Mac.

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Hello hattiejean, alan_r

alan_r said

You've got (out-of-the-Ark) Fx 3.6.28; I've got Firefox 44.0.2. I think this will explain nearly all of your problems. Someone else will give you the best advice on how to start again with Firefox for your Mac.

Confirm, alan_r is correct, the problem is definitely the 3.6.28 firefox, but hattiejean you can't install latest firefox, the one you use is the latest for your 10.4 Mac.

thank you

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You can use the third-party TenFourFox to be much more up to date and secure. http://www.floodgap.com/software/tenfourfox/

It is based on the Firefox 38.6.1 ESR release.

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The OP has an Intel Mac according to the user agent, so using TenFourFox isn't possible.

  • Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.4; en-US; rv:1.9.2.28) Gecko/20120306 Firefox/3.6.28

I don't know if you can update your Mac to OS X 10.6 to be able to install the current release.

Modified by cor-el

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Doh could have sworn it was PPC.