To open the about:config page, type about:config in the location (address) bar and press the "Enter" key, just like you type the url of a website to open a website.
If you see a warning then you can confirm that you want to access that page.
Re: My Browsing history only shows the last 7 days, how do I access more?
Yes I have done this, but it was the last 7-8 days I wanted specifically- Sat 29th Aug. But I think it's all gone forever sadly!!! I dont think there is any way to get it back as it is still saying only the last 2 days!!! Ive even restored to an earlier date and it still won't show anymore than 2 days, even when I havent deleted it. This is just Firefox if I had gone through internet explorer I would of found what I was looking for. Thanks for the help and advice - Heather x