FF version and what exactly is the screen of the error message?

I don't use LastPass myself, not because it's dodgy but because I still try to remember all my passwords. And reset the rest. ;-) Some of the reviews of the March 29th update to the LastPass add-on for Firefox indicate a need to roll back to the March 8th version. If you want to try that: (A) Disable auto-updates on LastPass on the Add-ons page. Either: * Ctrl+Shift+a (Mac: Command+Shift+a) * "3-bar" menu button (or Tools menu) > Add-ons * type or paste '''about:addons''' in the address bar and press Enter/Return In the left column of the Add-ons page, click Extensions. Then find LastPass on the right side and click its "More" link. Scroll down past the description to the settings, and you should find an option to change Automatic Updates from "Default" to "Off" (B) To install an older version, find its install button on the Versions page: https://addons.mozilla.org/firefox/addon/lastpass-password-manager/versions/ Hopefully you'll find one that works for you.