Firefox uses a built-in page named about:home (no http:// or https:// on that) which won't work in other browsers.

I mention that because the "Internet Options" control panel is for setting Internet Explorer settings, not Firefox settings.

If you need to change your home page within Firefox, see either of these articles:

• Startup, home page, tabs, and download settings
• How to set the home page

If Firefox is not following your setting, there may be a problem with an unwanted add-on. Please let us know the symptoms in more detail in that case.

Do you need to install Firefox? You can start here:

https://www.mozilla.org/firefox/

If your security software blocks that small "stub" installer, you can download the full installer from this page (scroll down to your preferred language):

https://www.mozilla.org/firefox/all/

See also;

• https://support.mozilla.org/kb/Browsing+basics
• https://support.mozilla.org/kb/Tabbed+browsing
• https://support.mozilla.org/kb/get-started-firefox-overview-main-features
• https://support.mozilla.org/kb/tabs-organize-websites-single-window