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Firefox is starting in a small window, and won't even run no matter what. Help?

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Okay, long story short, I accidentally downloaded some viruses. We got them removed (me and my father), but now, Firefox won't start! Well, it does, but it opens in a very small window, doesn't have the logo, and can't do anything but shrink. Please note, that not even Internet Explorer/Exploder could connect to the internet, so I'm using another computer.

                                                                                                                                          Best of luck,
                                                                                                                                                             Red (My nickname).
Okay, long story short, I accidentally downloaded some viruses. We got them removed (me and my father), but now, Firefox won't start! Well, it does, but it opens in a very small window, doesn't have the logo, and can't do anything but shrink. Please note, that not even Internet Explorer/Exploder could connect to the internet, so I'm using another computer. Best of luck, Red (My nickname).

All Replies (1)

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When you start Firefox, normally there is a thumbnail of your startup page above the Firefox button on the Windows 7/Windows 8 Task bar. Is that all you see, the actual window is nowhere to be found?

Thumbnail Only

Sometimes the Firefox window gets off-screen. If you have a multiple monitor setup, make sure both monitors are on. Other users have reported that sometimes Firefox behaves strangely when the second monitor is off.

In all other cases: Sometimes the Firefox window gets "off screen" somehow. You often can force it to appear on the screen by right-clicking the little thumbnail image above the Taskbar and choosing Maximize. Does that work?

One possible cause for this is that the file which stores window sizes and positions has become corrupted.

Method #1: If you can get a maximized window:

Open your current Firefox settings (AKA Firefox profile) folder using either

  • "3-bar" menu button > "?" button > Troubleshooting Information
  • (menu bar) Help > Troubleshooting Information
  • type or paste about:support in the address bar and press Enter

In the first table on the page, click the "Show Folder" button. This should launch a new window listing various files and folders in Windows Explorer.

Leaving that window open, switch back to Firefox and Exit, either:

  • "3-bar" menu button > "power" button
  • (menu bar) File > Exit

Pause while Firefox finishes its cleanup, then rename xulstore.json to something like xulstore.old. If you see a file named localstore.rdf, rename that one to localstore.old as well.

Start Firefox back up again. Do windows display normally again?

Method #2: If you cannot get a Firefox window at all:

Shut down Firefox by right-clicking the taskbar icon > Close All Windows.

Using the Run dialog (windows key + R) or the Start menu search bar (or in Windows 8 maybe the charms bar search bar?) type or paste the following and press Enter to drill down to the Profiles folder:

%APPDATA%\Mozilla\Firefox\Profiles

Here you may see one folder -- in which case, double-click into that -- or more than one folder -- in which case, double-click into what looks like the most recently updated.

Scroll down and rename xulstore.json to something like xulstore.old. If you see a file named localstore.rdf, rename that one to localstore.old as well.

Start Firefox back up again. Do windows display normally again?

Broken Window

If you get an actual Firefox window with missing features, try launching a new window using Ctrl+n. Also, try double-clicking the top bar to maximize the window. If neither works, please try the steps above for the Thumbnail problem.