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After upgrading to 8.0.1 Firefox will download but not install extensions after upgrading to 8.0.1

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  • 10 have this problem
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  • Last reply by roy_george

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Windows Vista. Avast Antivirus with Sandbox feature. Outside Sandbox - all extensions available. Within Sandbox - no extensions available and not able to install any extensions. ie Adblock Plus, No Script etc. Before upgrading to 8.0.1 no problems in either mode. Add-ons appear to be intact in either mode. When attempting to install an extension after downloading: "(extension) could not be installed because Firefox cannot modify the needed file". Reluctant to delete pluginreg dat file because all extensions are working outside Sandbox.

Windows Vista. Avast Antivirus with Sandbox feature. Outside Sandbox - all extensions available. Within Sandbox - no extensions available and not able to install any extensions. ie Adblock Plus, No Script etc. Before upgrading to 8.0.1 no problems in either mode. Add-ons appear to be intact in either mode. When attempting to install an extension after downloading: "(extension) could not be installed because Firefox cannot modify the needed file". Reluctant to delete pluginreg dat file because all extensions are working outside Sandbox.

Chosen solution

Sorry for the confusion. Please see this and this. It looks like there are issues on and off with the sandbox and Avast is aware and working on it.

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Hi,

You may have to "trust' the upgraded Firefox, if there is such a setting in Avast and install extensions after starting Firefox outside of the sandbox - normally. Not sure about Avast, but usually a sandbox would mean a virtual area like hard disk storage, registry settings etc. for the sandboxed app and once the application is closed or the computer is shutdown, everything that was done by the app or via the app is sort of vaporized and the application and it's settings are returned to it's previous permanent state.

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Thanks for the post Wilfred. (Have I got that right?). Already 'trusted site'. Firefox 8.0.1 has my extensions installed (automatically ported on upgrade). I simply choose to open Firefox without the Sandbox (All extensions activated) or within Sandbox (No extensions activated since upgrade). Pre-upgrade within sandbox (All extensions activated).

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Seçilmiş Həll

Sorry for the confusion. Please see this and this. It looks like there are issues on and off with the sandbox and Avast is aware and working on it.

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Thanks for the link. Problem not solved but at least you pointed me in the right direction. Seem Avast is the culprit in this. Strange though, working perfectly before the upgrade to Firefox 8.0.1