Hi China SeaDragon, required add-on signing for extensions is new in Firefox version 43. Back in February, it was announced that, for a safer add-on experience, all extensions will have to be verified and signed by Mozilla before they can be installed.

Unsigned extensions that are already installed will be automatically disabled. For more information, see Add-on signing in Firefox.

Extensions hosted on addons.mozilla.org are automatically signed. If an extension you wish to use is distributed by a third-party, it must be signed. Please ask the add-on developer or vendor if an updated and signed version of the add-on is available.

This signing requirement is mandatory in regular release and beta versions of Firefox. For testing purposes, it will still be possible to configure Firefox Developer Edition and Nightly versions to run unsigned extensions. For details, please see https://wiki.mozilla.org/Addons/Extension_Signing.

thank you

How far back did you roll your system?

Unfortunately, Windows' system restore feature can cause irreversible damage to your Firefox settings folder. If you are not able to make this work again, you may need to start fresh with a new profile (you can copy over data that is working).

Kaspersky extensions are included with your Kaspersky software. Firefox discovers them because Kaspkersky adds some entries to the Windows registry that Firefox checks. Perhaps the "restore" wiped out those entries? I suggest trying the following, in this order:

(1) Remove certain Firefox's settings file related to extensions that may have become corrupted. Steps below the line.

(2) If that doesn't work, reinstall your Kaspersky software (latest version). Then shutt down and restart Firefox to see whether it will now discover those extensions.

For #1: Open your current Firefox settings (AKA Firefox profile) folder using either

• "3-bar" menu button > "?" button > Troubleshooting Information
• (menu bar) Help > Troubleshooting Information
• type or paste about:support in the address bar and press Enter

In the first table on the page, click the "Show Folder" button. This should launch a new window listing various files and folders in Windows Explorer.

Leaving that window open, switch back to Firefox and Exit, either:

• "3-bar" menu button > "power" button
• (menu bar) File > Exit

Pause while Firefox finishes its cleanup, then rename any of these files that you find:

• compatibility.ini to something like compatibility-old.ini
• extensions.ini to something like extensions-old.ini
• extensions.json to something like extensions-old.json
• extensions.sqlite to something like extensions-old.sqlite (might not exist depending on how long you've been using this settings folder)

When you start Firefox back up again, it should explore your profile folder, other folders, and the Windows registry to rebuild the list. It probably will ask you to approve some of the extensions. Once things settle down, do you have your old extensions back?

Note: Since the Kaspersky extensions are not signed, when you update to Firefox 43, you will need to make a temporary exception to the signing requirement until they get updated. This is global for all extensions, there's currently no way to only make an exception for one specific extension.

(1) In a new tab, type or paste about:config in the address bar and press Enter/Return. Click the button promising to be careful.

(2) In the search box above the list, type or paste xpin and pause while the list is filtered

(3) Double-click the xpinstall.signatures.required preference to switch it from true to false -- note that this is for Firefox 43 only

As for Roll-Back it was about 15 min, as I created a restore point specifically to try to avoid problems - silly me.

I appreciate the detailed help. This may let me upgrade to 43 and then get Kaspersky running again, and maybe even let me get all my addons back.

IF I were to just delete FF from my computer, is there a place to get FF42 install file, or do I have to go to FF43? As you might guess I may have a better experience with 43, but I am skeptical right now. so far I have lost a full day trying to fix this fiasco. They may have announced it, but I did not see any e-mail talking about this.

Again, thank you for the help, I'll let you know if I GET IT WORKING.

jscher2000 said

Note: Since the Kaspersky extensions are not signed, when you update to Firefox 43, you will need to make a temporary exception to the signing requirement until they get updated. This is global for all extensions, there's currently no way to only make an exception for one specific extension. (1) In a new tab, type or paste about:config in the address bar and press Enter/Return. Click the button promising to be careful. (2) In the search box above the list, type or paste xpin and pause while the list is filtered (3) Double-click the xpinstall.signatures.required preference to switch it from true to false -- note that this is for Firefox 43 only

B-I-N-G-O!!!!! I have it ALL back! THANK YOU!! This Solved my problem!