If you have set Mozilla Firefox to use proxy servers yourself or some malware infected your computer and has set its own redirecting proxy servers, and you want to disable the proxy servers then you can follows these simple steps.
- Start your your Firefox browser.
- Select from the menubar Tools → Options.
- In the Options window, select Advanced → Network tab. Then click on the Settings button as shown :
- Check the option No Proxy on the top as shown
- Click OK to save the settings. Close the Options window.