Let's start with this; https://support.mozilla.org/en-US/kb/how-to-fix-preferences-wont-save

Note: Some software, like Advanced SystemCare with Surfing Protection, can protect files in the Firefox profile folder against changes. If you have such software then check the settings or uninstall this software.

donyaaaa said

I have encountered a new problem. Previously could not get new tabs to go directly to my home page of google and with some great advice and support downloaded the tab override addon, where I was told I had adjust the settings for that addon which I did by going through addons, extensions etc but now all of a suddent the override tab once again just stopped working and I simply am back to a blank page on every new tab. I have gone to the button on the top right with 3 horizontal lines clicked on addons and extensions where I clicked on the override addon its set as default, went to click on options and it just goes to a page which says I have the wrong address?? So where please tell me exactly where are the settings for this override addon because as I said the options button I would have thought would be where I find the settings?? which when clicked on goes to 'this page is not valid'. Please advise, thanks again

Thank you, I looked up what you said and realized it could be the CCleaner, so I uninstalled it restarted the computer and ...voila! it works again!! Thanks so much again.

Glad to help. Safe Surfing.