Sorry to hear about the hijacking. If you observe the address bar drop-down as you are typing your query, does it say it will send searches to Google -- so the hijacking is occurring after you submit the query -- or does it already say it will use Yahoo (or one of Yahoo's affiliates that directs results to Yahoo)? In the case that it's already wrong, see: [[Change your default search settings in Firefox]] In the case that it's hijacked after submission, the typical culprit would is an extension. You can view, disable, and often remove unwanted or unknown extensions on the Add-ons page. Either: * Ctrl+Shift+a (Mac: Command+Shift+a) * "3-bar" menu button (or Tools menu) > Add-ons * type or paste '''about:addons''' in the address bar and press Enter/Return In the left column of the Add-ons page, click Extensions. On the right side, find the "Manage Your Extensions" heading. ''If there is at least one extension before the next heading -- "Recommended Extensions" -- please continue:'' Then cast a critical eye over the list below that heading. Any extensions Firefox installs for built-in features are hidden from this page, so everything listed here is your choice (and your responsibility) to manage. Anything that mentions search, or privacy, or looks suspicious, or that you just do not remember installing or why? If in doubt, disable (or remove). For your privacy and security, don't let mystery programs linger here. '''** What if this panel is blank or missing? **''' You can restart Firefox in its Troubleshoot Mode to temporarily disable all add-ons to prevent interference. See: [[Diagnose Firefox issues using Troubleshoot Mode]]. Any improvement?