Is it listed in the Add-ons Manager as disabled?

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

Is it the version from Yahoo's own site or the Mozilla Add-ons site, which I think is more recent now:

https://addons.mozilla.org/firefox/addon/yahoo-toolbar/

The other day I saw several threads where users said they could enable Yahoo for their current session, but when they closed the last Firefox window and started Firefox again, the extension was disabled. If you check the Add-ons page, is that the pattern you're seeing? Either:

• Ctrl+Shift+a
• "3-bar" menu button (or Tools menu) > Add-ons

In the left column, click Extensions. Then check at the bottom of the list on the right side for a disabled Yahoo Toolbar extension and see whether you can enable it there.

brill that works thanks

Glad to help. Safe Surfing.

Windows 10, Mac. Doesn't matter. Anytime the computer updates anything Yahoo Tool bar as an add-on goes away and you need to reinstall it.

Please fix! I love getting calls every day from my parents in another state asking where are their bookmarks!

razzzy said

Windows 10, Mac. Doesn't matter. Anytime the computer updates anything Yahoo Tool bar as an add-on goes away and you need to reinstall it. Please fix! I love getting calls every day from my parents in another state asking where are their bookmarks!

The Yahoo toolbar add-on becoming disabled in Firefox 43 is a known issue that Mozilla and Yahoo are working on. In this particular case you can follow the instructions for advanced users in the Add-on signing in Firefox article (toggle the xpinstall.signatures.required preference to false in the Firefox configuration Editor) but this is only a temporary solution which will no longer work in Firefox 44 future Firefox versions.

You are replying to a solved thread. If you need more help you'll need to ask your own question. See Mozilla Support rules and guidelines.

There's been an update to the Yahoo toolbar add-on that resolves the problem. If you have set the xpinstall.signatures.required preference to false in the Firefox Configuration Editor (about:config page) as a workaround, you can go back now and reset the preference back to true.