Could you: (1) Visit the Windows Control Panel, Uninstall a Program and click the "Installed on" column heading to group by date. I suspect you will find unwanted and probably undisclosed bundle items (AKA garbage) that snuck in with some free software. Remove what you can. (2) Scan using some of the effective free cleanup programs listed in our support article: [[Troubleshoot Firefox issues caused by malware]]. Note: don't remove places.sqlite or bookmarks-2014....json files that the cleaning programs may recognize as having history or bookmarks of bad sites because this could clear all your bookmarks. (3) Start Firefox back up again and check for any lingering problem extensions on the Add-ons page. Either: * Ctrl+Shift+a * "3-bar" menu button (or Tools menu) > Add-ons In the left column, click Extensions. Then you can disable all nonessential or unrecognized extensions. Usually a link will appear above at least one disabled extension to restart Firefox. You can complete your work on the tab and click one of the links as the last step. (4) Finally, to reset your home page, search service, and new tab page to their defaults, you can use this one-click solution: [https://addons.mozilla.org/firefox/addon/searchreset/]. If you prefer to do that by hand, we can post the steps. Does that flush the ads?