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Cannot install Lastpass add-on

  • 5 replies
  • 1 has this problem
  • 1 view
  • Last reply by FredMcD

lyrussel
lyrussel
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Since upgrading to FF42 (now on FF43) I haven't been able to install FF - either from the add-on tab or from lastpass's site. I have done a FF clean install; I have done FF refresh. I can install on Chrome without issue, but firefox is my preferred browser. I have contacted Lastpass and they have tried to resolve the issue, but it installs for them without issue. I am on Windows 7.

The attached powerpoints show the error messages. If I try from the add-on page, I get "There was an error installing lastpass". If I use the link lastpass provided (https://addons.mozilla.org/en-US/firefox/addon/lastpass-password-manager/) I get "LastPass could not be installed because Firefox cannot modify the needed file).

Since upgrading to FF42 (now on FF43) I haven't been able to install FF - either from the add-on tab or from lastpass's site. I have done a FF clean install; I have done FF refresh. I can install on Chrome without issue, but firefox is my preferred browser. I have contacted Lastpass and they have tried to resolve the issue, but it installs for them without issue. I am on Windows 7. The attached powerpoints show the error messages. If I try from the add-on page, I get "There was an error installing lastpass". If I use the link lastpass provided (https://addons.mozilla.org/en-US/firefox/addon/lastpass-password-manager/) I get "LastPass could not be installed because Firefox cannot modify the needed file).

All Replies (5)

FredMcD
FredMcD
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This will disable add-on signature enforcement; Enter about:config into your Firefox address bar Click the I'll be careful button Find xpinstall.signatures.required in the list Right click the preference Select Toggle until the value is false https://support.mozilla.org/en-US/kb/add-on-signing-in-firefox

https://wiki.mozilla.org/Firefox/AddOns/Status/Updates#Exec_Summary “Currently targeting Signing with no pref to turn off in Firefox 47”

lyrussel
lyrussel Question owner
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Thanks Fred - have just tried this but same result - still cannot install and throws the same error messages.

FredMcD
FredMcD
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Contact their support site for more help, or a reason for the error.

lyrussel
lyrussel Question owner
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I did - and they routed me here. They have no idea what is causing it.

FredMcD
FredMcD
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I've called the big guys to help you. Good luck.