Hi, this could be caused by having Fastmail set as your home page in Firefox. If you get the page every time you launch a new window with Ctrl+N, then that's definitely the first thing to check. You can try the steps in the following article to change your home page: [[How to set the home page]]. If you only get Fastmail at startup, is it a "pinned" tab? Pinned tabs look different because they only have an icon and not a title up on the tabs bar. To unpin a tab, right-click the tab and choose Unpin. Then you should be able to change site or close it like a normal tab. More info on pinned tabs: [[Pinned Tabs - keep favorite websites open and just a click away]]. Another possibility is that you have an add-on which promotes that site for some reason. See: [[Troubleshoot issues related to add-ons]]. Finally, it's possible the shortcut you use to start Firefox has been modified to load Fastmail. If you right-click the shortcut and choose Properties, Windows should display the Shortcut tab (or you can click Shortcut). The Target line usually is quite simple: "C:\Program Files\Mozilla Firefox\firefox.exe" If yours has any extra text after that, it might be the source of the problem. Any luck so far?