Hello,

Other users with a similar problem had malware that caused it. First check your extensions and remove any suspicious ones:

• Tools (or ) > Add-ons > Extensions

Try scanning with free tools such as:

• MalwareBytes' Anti-Malware
• AdwCleaner (for more info, see this alternate AdwCleaner download page)
• Anti-Rootkit Utility - TDSSKiller
• Microsoft Safety Scanner
• Hitman Pro
• ESET Online Scanner

Further information can be found in the Troubleshoot Firefox issues caused by malware article.

Did this fix your problems? Please report back to us!

I did this... nothing has changed.

Is it only Firefox that has this problem? If so, try Firefox Safe Mode to see if the problem goes away. Firefox Safe Mode is a troubleshooting mode that turns off some settings, disables most add-ons (extensions and themes).

If Firefox is open, you can restart in Firefox Safe Mode from the Help menu:

• Click the menu button , click Help and select Restart with Add-ons Disabled.

If Firefox is not running, you can start Firefox in Safe Mode as follows:

• On Windows: Hold the Shift key when you open the Firefox desktop or Start menu shortcut.

When the Firefox Safe Mode window appears, select "Start in Safe Mode".

If the issue is not present in Firefox Safe Mode, your problem is probably caused by an extension (or combination of), and you need to figure out which one. Please follow the Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems article to find the cause.

To exit Firefox Safe Mode, just close Firefox and wait a few seconds before opening Firefox for normal use again.

When you figure out what's causing your issues, please let us know. It might help others with the same problem.

If the problem still occurs in safe mode, can you go to your troubleshooting page either by:

• Entering about:support in the address bar, or
• Going to Help (or > ) > Troubleshooting Information

Near the top should be buttons to copy information to the clipboard; could you click on one of them and paste them here? No personal information is collected, and it might be able to show us what could be causing the problem.

Running Firefox in safe mode did NOT solve the issue. I have copied to the clipboard. Let me know what else to do.

After clicking one of those buttons to copy, can you paste that information here as a reply?

{

 "application": {
   "name": "Firefox",
   "version": "34.0",
   "userAgent": "Mozilla/5.0 (Windows NT 6.0; WOW64; rv:34.0) Gecko/20100101 Firefox/34.0",
   "supportURL": "https://support.mozilla.org/1/firefox/34.0/WINNT/en-US/",
   "numTotalWindows": 1,
   "numRemoteWindows": 0
 },
 "crashes": {
   "submitted": [
     {
       "id": "bp-c0ef15b4-857e-40ae-86aa-2dd3c2141109",
       "date": 1415547949691,
       "pending": false
     }
   ],
   "pending": 0
 },
 "modifiedPreferences": {
   "browser.cache.disk.capacity": 358400,
   "browser.cache.disk.smart_size.first_run": false,
   "browser.cache.frecency_experiment": 1,
   "browser.places.smartBookmarksVersion": 7,
   "browser.sessionstore.upgradeBackup.latestBuildID": "20141106201515",
   "browser.startup.homepage_override.mstone": "34.0",
   "browser.startup.homepage_override.buildID": "20141106201515",
   "dom.mozApps.used": true,
   "extensions.lastAppVersion": "34.0",
   "media.gmp-gmpopenh264.lastUpdate": 1415562788,
   "media.gmp-gmpopenh264.version": "1.1",
   "media.gmp-manager.lastCheck": 1415562787,
   "network.cookie.prefsMigrated": true,
   "places.history.expiration.transient_current_max_pages": 104858,
   "plugin.disable_full_page_plugin_for_types": "application/pdf",
   "plugin.importedState": true,
   "privacy.sanitize.migrateFx3Prefs": true
 },
 "lockedPreferences": {},
 "graphics": {
   "numTotalWindows": 1,
   "numAcceleratedWindows": 0,
   "windowLayerManagerType": "Basic",
   "windowLayerManagerRemote": true,
   "numAcceleratedWindowsMessage": [
     "tryNewerDriver",
     "7.1500.1000.1666"
   ],
   "adapterDescription": "Mobile Intel(R) 4 Series Express Chipset Family",
   "adapterVendorID": "0x8086",
   "adapterDeviceID": "0x2a42",
   "adapterSubsysID": "02aa1028",
   "adapterRAM": "Unknown",
   "adapterDrivers": "igdumd64 igd10umd64",
   "driverVersion": "7.15.10.1637",
   "driverDate": "1-16-2009",
   "adapterDescription2": "",
   "adapterVendorID2": "",
   "adapterDeviceID2": "",
   "adapterSubsysID2": "",
   "adapterRAM2": "",
   "adapterDrivers2": "",
   "driverVersion2": "",
   "driverDate2": "",
   "isGPU2Active": false,
   "direct2DEnabled": false,
   "directWriteEnabled": false,
   "directWriteVersion": "7.0.6002.23200",
   "direct2DEnabledMessage": [
     "tryNewerDriver",
     "8.1500.1000.2202"
   ],
   "webglRendererMessage": [
     "tryNewerDriver",
     "7.1500.1000.1666"
   ],
   "info": {
     "AzureCanvasBackend": "skia",
     "AzureSkiaAccelerated": 0,
     "AzureFallbackCanvasBackend": "cairo",
     "AzureContentBackend": "cairo"
   }
 },
 "javaScript": {
   "incrementalGCEnabled": true
 },
 "accessibility": {
   "isActive": false,
   "forceDisabled": 0
 },
 "libraryVersions": {
   "NSPR": {
     "minVersion": "4.10.7",
     "version": "4.10.7"
   },
   "NSS": {
     "minVersion": "3.17.2 Basic ECC",
     "version": "3.17.2 Basic ECC"
   },
   "NSSUTIL": {
     "minVersion": "3.17.2",
     "version": "3.17.2"
   },
   "NSSSSL": {
     "minVersion": "3.17.2 Basic ECC",
     "version": "3.17.2 Basic ECC"
   },
   "NSSSMIME": {
     "minVersion": "3.17.2 Basic ECC",
     "version": "3.17.2 Basic ECC"
   }
 },
 "userJS": {
   "exists": false
 },
 "extensions": [
   {
     "name": "LastPass",
     "version": "3.1.1",
     "isActive": true,
     "id": "support@lastpass.com"
   },
   {
     "name": "AVG Web TuneUp",
     "version": "3.1.0.7",
     "isActive": false,
     "id": "avg@toolbar"
   },
   {
     "name": "McAfee Security Scan Plus",
     "version": "1.0",
     "isActive": false,
     "id": "{e4f94d1e-2f53-401e-8885-681602c0ddd8}"
   },
   {
     "name": "Microsoft .NET Framework Assistant",
     "version": "0.0.0",
     "isActive": false,
     "id": "{20a82645-c095-46ed-80e3-08825760534b}"
   },
   {
     "name": "SmartPrintButton",
     "version": "1.0",
     "isActive": false,
     "id": "quickprint@hp.com"
   }
 ],
 "experiments": []

}

Any thoughts?

Unfortunately I can't seem to find anything wrong. I have been looking at posts by people with the similar problem:

• One solved by updating Java
• Another solved by running AdwCleaner (see my first post for the link)
• There is a bug report for this issue as well: https://bugzilla.mozilla.org/show_bug.cgi?id=933733
  • From: https://support.mozilla.org/en-US/questions/1018521

Solved by removing add-ons/malware scans:

• https://support.mozilla.org/en-US/questions/1019045
• https://support.mozilla.org/en-US/questions/1018259

Solved by Java

• https://support.mozilla.org/en-US/questions/1028006

Can you try running Windows Safe Mode with network support (press F8 on the boot screen) as a test to see whether some other application might be interfering with Firefox?

• http://www.bleepingcomputer.com/tutorials/how-to-start-windows-in-safe-mode/

You can also try using the latest stable release to see if its something in the beta causing the issue:

• https://www.mozilla.org/en-US/firefox/all/

I don't understand.

I don't know what the boot screen is and I'm not sure I've made anything better at all.

If you are using Windows 8, please follow these instructions: http://www.bleepingcomputer.com/tutorials/start-windows-8-in-safe-mode/

Otherwise, for all other Windows versions, when your computer starts/restarts a screen shows up displaying your hardware information, BIOS version, etc. When you see this screen gently and repeatedly press F8 until you are shown a Windows menu asking how you want to boot up your computer. When that screen appears, press the down arrow key until "Safe Mode with Networking" is selected, and then press Enter. After Windows loads up, start Firefox and see if you still have your issue.

More information about starting Windows in safe mode is presented in the link posted earlier: http://www.bleepingcomputer.com/tutorials/how-to-start-windows-in-safe-mode

I am using Windows Vista Home and I have no idea what screen I am supposed to push F8. I've tried restarting and pushing it at various times, but there's no screen that shows up displaying my hardware information, etc as you described. I am really struggling here! And have been working on this ALLLLLLL day!

You can try the alternate method of getting into Safe Mode:

• Close any running programs and open Windows so you are back at the desktop.
• Click on the Start button.
• In the Start Menu Search Box type msconfig and press enter on your keyboard.
• Click on the Boot tab.
• Check off "Safe boot" and it should enable the radio buttons below - select "Network"
• Press Apply and OK
• A dialog should appear asking you to restart, do so and your computer should shut down and start up in safe mode

After you are done checking Firefox:

• Close the programs, and still in Safe Mode, open the Start Menu
• In the Search Box and type msconfig and press enter on your keyboard.
• Under the General tab, select Normal Startup
• Press Apply and OK
• Reboot and you will be back in normal mode

What do I do when I'm in safe mode?

Open Firefox and see if you still have a problem. If you don't, then it is likely an application outside of Firefox that is causing it to hang like that and you will need to figure out what it is (likely an antivirus application).

I did not have the problem in safe mode. So, now what?

Run AdwCleaner (for more info, see this alternate AdwCleaner download page) to make sure its not adware.

If that doesn't fix it still, then check your antivirus, you'll have to see your settings yourself to see what it is that is interfering with Firefox. Unfortunately if Firefox is working in Windows Safe Mode, it looks like what is causing the problem is external to Firefox so I don't know where to go from here.

Maybe you can research what running in Windows Safe Mode does in the links I provided earlier to see what services Windows prevents from loading up and help you narrow down what programs on your computer you need to look into. Copying from the link I sent you earlier: Windows Safe Mode is a way of booting up your Windows operating system in order to run administrative and diagnostic tasks on your installation. When you boot into Safe Mode the operating system only loads the bare minimum of software that is required for the operating system to work. This mode of operating is designed to let you troubleshoot and run diagnostics on your computer. Windows Safe Mode loads a basic video drivers so your programs may look different than normal.