Some problems occur when your Internet security program was set to trust the previous version of Firefox, but no longer recognizes your updated version as trusted. Now how to fix the problem: To allow Firefox to connect to the Internet again;

• Make sure your Internet security software is up-to-date (i.e. you are running the latest version).
• Remove Firefox from your program's list of trusted or recognized programs. For detailed instructions, see

Configure firewalls so that Firefox can access the Internet. {web link}

The Firefox version was unmodified; there was NO update; so "but no longer recognizes your updated version as trusted" does not apply.

As said,

• All Windows components are up-to-date
• I disabled Windows Defender / Firewall as far as possible and it did not help.
• I meanwhile completely replaced Windows Defender / Firewall by Bitdefender (which comes with its own, plain rule set) and it did not help.
• The problem only affects the windows standard user account. On the windows admin user account, there has never been any problem like this. (Windows Defender / Firewall uses the same set of rules for all windows user accounts, as far as I know; at least the fresh installed BitDefender does so.)

hello ti,

i assume that other browsers on your system are not effected by malfunction?

one of the initial things that i would do is to ensure there is no issue resulting from a lack of resources, like memory and space.

what i suggest to open the windows start up manager and disable "everything" that is starting up with the desktop. if you have a mouse driver and graphics driver, leave these alone.

also, double check the pagefile / virtual memory size and ensure the size recommendations cited in the pagefile window are being invoked.

also, create a c:\temp folder and then change the variables of the environment and system paths for the temp folder to c:\temp

then reboot and see how FF behaves.

if still no good, i think we can continue the process of elimination.

~dbben, with your ideas, I could trace back the problem a step further.

(Note: my Windows is in german, I hope my english translations of the german terms are correct.)

When entering "msconfig" in the search box, go to "Dienste" (Services) and disable "Jugendschutz" (Youth Protection). Then everything works fine again.

Is there a known conflict between Firefox and Windows' youth protection service? I have no idea where one can adjust the youth protection settings. I can only access the Safe Search Settings in the Windows Settings. I tried lowering from strict to medium, but this does not help.

By the way, I discovered that the problem also affects Opera GX while it does NOT affect Edge. (Honi soit qui mal y pense ...)

Additional note: Because the Youth Protection service may take some time for startup, when starting Firefox immediately right after login, it may show up its window properly at first glance. As soon, as Youth Protection is running, it shuts down Firefox. In these cases it seems as if a running Firefox closes all of a sudden.

hello ti,

Thank you for updating us with your findings.

While I am not familiar with "youth protection", I believe that it is an application that protects "youths" from the dangers of the internet.

It might be like Google's safe search option, whereas google search results wont produce pornographic images or images that are emotionally horrible.

I believe window 10 also has a built-in mechanism that is used by parents to protect their kids while using the computer.

However, since i dont have kids and have no issues with seeing nasty pictures, I dont know how this feature to protect kids works.  :-)

I hope the above enlightens you a bit more on what likely was occurring with your system.

While we do not always have all the answers, we are hear to help as much as we can. And ultimately, the FireFox programming teams will read threads like yours here and gain a better understanding of what is going on.

Again, thanks for sharing !!