Hello royalnutrition, I hope these articles can help: [https://support.mozilla.org/en-US/kb/make-firefox-your-default-browser#firefox:win10:fx72 Make Firefox your default browser] [https://support.mozilla.org/en-US/kb/setting-firefox-default-browser-does-not-work#firefox:win10:fx72 Setting Firefox as the default browser does not work - What to do] [https://support.mozilla.org/en-US/kb/keep-flash-up-to-date-and-troubleshoot-problems#firefox:win10:fx72 Flash Plugin - Keep it up to date and troubleshoot problems]

Hello, there is no way for help with these article !! Please give me other option for setting firefox as default browser

Hello again, Try reinstalling Firefox: [https://support.mozilla.org/en-US/kb/troubleshoot-and-diagnose-firefox-problems#w_4-reinstall-firefox Reinstall Firefox] then, see if you can set it as your default browser.