Hi Bill, could you describe the problem in a little more detail?

If you check the explanation on the Add-ons page, why is the Kaspersky Protection extension disabled? You can view that using either:

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

In the left column, click Extensions. Then scroll down on the right side (disabled extension are at the bottom of the list).

If the Add-ons page indicates the problem is that the extension is not verified:

Firefox 43+ requires that extensions be digitally signed by Mozilla. This article has more information: Add-on signing in Firefox. Kaspersky is said to be working on making that happen.

Until it does, you can make a global exception to the signing requirement (there's currently no way to only make an exception for specific extensions).

(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 43-45 only

I sent 2 Separate E-Mail Replies - No GO! Reply 1 - Copy Sure I can elaborate . . . The web page says (and I quote) :

 ! Kaspersky Protection could not be verified for use in Firefox and has been disabled.       [ More Information - Link ]
(Hex)  Kaspersky Protection (disabled)  -   Your protection on the Internet with extension from Kaspersky Lab . . .     [ More - Link ]
and that's it.

The "More Info." page just takes you to "Add-on signing in Firefox 45" ?? > Amazing - Firefox lets Facebook, Yahoo, and Google run loose without supervision ! That is like giving a Loaded (Condition 1) .45ACP 1911 Side-arm to a 5 year old ! Kaspersky is the ONLY one out of that whole bunch that I trust.

Reply No. 2 - Copy Hello, again.

 I went ahead and followed your directions for  "Double-click the xpinstall.signatures.required preference to switch it from true to false" 

That is certainly 100 times Safer than running a browser (any browser) without the Kaspersky protection. I guess this means that I Can NEVER Update Firefox - EVER Again ! - Can I set that up for permanent status ? I can always use just Opera and MS-IE. Never, Never will I use Chrome or Safari ! Thank You for All the Help ! Take Care. Bill M

Note that the kapersky extensions that are installed in your browser do nothing to increase your security, but are only a way for the anti-virus makers to make more money through search revenue and data mining. The actual anti-virus that actually protects your computer runs in the background and runs no matter what browser you are using (or if you are even using a browser at all). Disabling signatures or not updating your browser leaves you at risk for worse attacks that anti-virus can't protect against.

Hi Bill, two things:

(1) Kaspersky is going to get its extension signed, it's just a matter of time. They know about this workaround, so it seems they aren't feeling the crunch yet.

(2) The new Kaspersky Protection extension is focused on the "Protected Browser mode" feature -- do you use this feature? -- while all the heavy lifting of protecting your system from malware is done outside of Firefox, through real-time scanning of disk writes and pre-filtering of all your web requests.

I have just received (Very recently) Some Clear and "To-the-Point" information and guidance from two Very Knowledgeable Gentlemen. I personally, have misjudged Firefox and their support structure - and I am more than willing to apologize. I am Sorry ! Thanks to Both men for their support and for your patience with the Less Well informed. God Bless. Bill M