Firefox "can't load XPCOM" - even with complete fresh reinstall

Gaz1701 · 20 Jun 2017

I have tried seemingly everything bar reinstalling Windows 10 to try to get Firefox to work again.

I've moved my profile to an external HDD, and deleted everywhere I know that Firefox is located:

C:\Program Files\Mozilla Firefox (OR)
C:\Program Files (x86)\Mozilla Firefox
C:\Users\*username*\AppData\Local\Mozilla\Firefox
C:\Users\*username*\AppData\Local\Mozilla\updates
C:\Users\*username*\AppData\Local\VirtualStore\Program Files\Mozilla Firefox
Plus even the 'roaming' ones, too

AND used the Advanced scan with Revo Uninstaller to remove every other trace of Firefox - registry included.

But after [the ridiculously long process of] reinstalling firefox, the same error message still keeps appearing!
I've ran out of ideas (and running out of patience) as to why it still keeps saying this.

I don't know if it's just because my computer's so old or not, but seems to take at least something like 10 minutes to install it! And to keep on trying to uninstall it and reinstalling it all the time seems to take forever.

Any help will be much appreciated. I don't like the other webbrowsers, and for the time being I'm using a Mozilla-based on called CLIQZ - but I can't install any addons to it, as it's a "privacy browser".

*edit* sorry, didn't see the 'Browsers and Email' section there, my bad

Josey Wales · 20 Jun 2017

https://developer.mozilla.org/en-US/docs/Mozilla/Tech/XPCOM

Maybe this will help

Mozilla-based on called CLIQZ

never heard of it. I use Fx 54.0 64 Bit

Not Myself · 20 Jun 2017

If you go to Index page mozillaZine Forums and type "xpcom" (without the quotation marks, cf course,) in the box entitled Search Boards" on the right side of the screen, you will see a lengthy set of replies, some of which might have useful information for you.

Gaz1701 · 25 Jun 2017

Sorry for the late reply, I've tried the suggestions they put on there:

Close all applications and reboot the computer.
Delete any downloaded or partially downloaded installer files.
Clear the browser cache (of whatever browser you are using to download FF) and the Windows Temp directory.
Shutdown any anti-virus software you are running.
Download a new copy of the full installer from [Firefox's download page]
Run the installer.
Restart the anti-virus program.

It worked ONCE [and once only], but after restarting Firefox, the same message appears again! I've posted what I've done so far on their forums

Ps. Thanks for the info on what XPCOM is Josey Wales, but there's far too much to read - and I don't really understand it anyway (or how it could be useful to me)

Josey Wales · 25 Jun 2017

Gaz1701 said:

Sorry for the late reply, I've tried the suggestions they put on there:

It worked ONCE [and once only], but after restarting Firefox, the same message appears again! I've posted what I've done so far on their forums

Ps. Thanks for the info on what XPCOM is Josey Wales, but there's far too much to read - and I don't really understand it anyway (or how it could be useful to me)

Then why care if you can't open it??

pyramid10 · 25 Jun 2017

You may want to visit palemoon dot org, and check out their browser(s) as alternative(s) to the privacy browser you are now using.

Mozilla/Firefox is moving closer to a WebExtension add-on only browser (version 57?).

Pale Moon, as a forked Firefox browser and further developed independently from Mozilla, can accept non-WebExtension add-on's with the exception of JetPack add-on's. And no Australis! Progress has its gains and losses.

Gaz1701 · 03 Jul 2017

I don't quite know how I've gotten it to work, but I've had much bigger issues with the internet on my Desktop not working - but I'll post that as a separate thread in the relevant place.

Thanks for the suggestion pyramid10, I'll have to try it out :)