Marc_W wrote:The desktop runs a pentium 4 chip I think,
According to https://en.wikipedia.org/wiki/Pentium_4
, that desktop supports SSE2. It should be capable of running the latest version of Firefox.
I suggest you give the latest Firefox a try, as follows:
1) Completely quit Firefox, then copy C:\Documents and Settings\<you>\Application Data\Mozilla\Firefox\
to an external disk.
2) Eject the external disk.
3) Download the latest version of Firefox
. Don't install it yet.
4) Into Windows Control Panel > Add or remove programs, and uninstall your existing Firefox. Make sure you select to KEEP your personal data.
5) Once that's done, install the Firefox you downloaded in (3).
Can't make the latest Firefox work for you? Here's how to revert back to version 28 -
1) Windows Control Panel > Add or remove programs. Uninstall Firefox.
2) Reinstall Firefox 28 from your installer. If you don't have the installer, get one from https://ftp.mozilla.org/pub/firefox/releases/28.0/
3) Delete the folder C:\Documents and Settings\<you>\Application Data\Mozilla\Firefox\
, if it exists. Then copy in the backup you made.
4) Start Firefox and double check that it's working.