Someone might want to have a look at this 
I did a Google search for a topic here at the Avast forum and when I clicked on the link FireFox said:
This connection is untrusted (see image)
By the way, when I clicked on my FireFox bookmark for Avast forum I did not get that message (all bookmarks are trusted I guess)
All the best, woz of oz
I don’t see what link you clicked to get that message. It may have helped if you had included it. But maybe it’s not necessary. I get that message if a link to the forum uses https instead of http. Clicking on Technical Details tells me:
forum.avast.com uses an invalid security certificate.The certificate is not trusted because it is self-signed.
Just change the https in the link to http. It should work all right then.
What program was responsible for this POP-up certainly not firefox itself, as I have never seen this pop-up, some add-on perhaps ?
I think that the link you clicked on was https and not the normal http which shouldn’t be an issue. The site only has a local self certified https certificate, so that is likely to be the reason.
It’s a Firefox popup, David. Click on this link and a page similar to the OP’s comes up. Looks like a version that’s different from Fx 3.6.3 on Windows XP or else a non-default theme is being used.
https://forum.avast.com/index.php?topic=60319.msg508745#msg508745
I think that the link you clicked on was https and not the normal http which shouldn't be an issue. The site only has a local self certified https certificate, so that is likely to be the reason.
Is this different from what I said already? Anyhow, thank you for your agreement.
It’s Firefox… just try https:\forum.avast.com
Yes, he used the https.
That is why I mentioned it as the default pop-up is very different (certainly on my ff 3.6.3), one which I have seen before and I believe more meaningful as far as the self signed certificate.
If I use the https the warning is pretty similar to the wozofoz warning.
Well that was fun ;D
Same result…https thing
I’m still baffled as to where these different screens are generated as I see nothing in the default firefox settings.
The smurf’s screenshot is the first that looks as mine does.
Mine is identical.
Mine too.
It looks like you’re getting a popup dialog, David. The rest of us are getting an error screen displayed in a tab or new window, the default behavior. I think there may be an about:config preference which can cause it to be displayed as a dialog popup like yours instead.
Also, the red and blue buttons in your dialog look like something produced by a non-default theme. What are you doing to get an OK button that looks like that?
Edit: Found it! Toggling the about:config pref browser.xul.error_pages.enabled to false gives me a dialog similar to yours, David – except for the difference in theme, of course.
Yes Alan that is the beast, I can’t recall ever having changed it, but it ‘is’ a user set value to display the popup rather than load a page to display the error.
The Blue OK button is I believe from my Noia 2.0 theme/skin, I don’t know about the Red (stop signal style icon) button though.
Thanks for the detective work.
Edit: I have changed it back to the default as that allows for other options, acceptance of the risk and allowing the site, etc. This is more flexible than the user set option, which only allows acknowledgement of the warning (OK) and no display of the page. I really have no idea how this changed, I hate mysteries.
You’re welcome.
In my case, that’s often due to a memory error. 
My long term memory is still very good, if only I could remember where I put the to do list ;D
Gee wiz 14 replies, sorry I haven’t replied sooner.
I didn’t check back here for a while because I figured the reply would be just Thanks we know and that’s just the way it is or Thanks we will look into it type thing
Thanks for the answer, it’s much appreciated
I only mentioned the alert here because I thought if someone who doesn’t use Avast but was interested in learning more about Avast by coming to the forum saw this message, they might be put off the forum and possibly the software.
Yep it was a https address
FireFox is version 3.6.3
My FireFox theme is SilverMel but I don’t need (so deleted) the extension extras. It’s a good compact theme if you have a small 9" NetBook like I do and it looks nice (I think)
@ http://addons.mozilla.org/en-US/firefox/addon/7517/
The question is answered and everyone seems to have had a nice chat about it, so all is good
All the best, woz of oz
Welcome to the forums.