Thank you for submitting crash reports. In order to share them with volunteers, could you try following the steps below to provide us crash report IDs:

1. Enter about:crashes in the Firefox address bar and press Enter. A Submitted Crash Reports list will appear, similar to the one shown below.
2. Copy the 5 most recent Report IDs that start with bp- and then go back to your forum question and paste that into the "Post a Reply" box. (Please don't take a screenshot of your crashes, just copy and paste the ID's. The below image is just an example of what your Firefox screen should look like)

Thank you for your help!

More information and further troubleshooting steps can be found in the Troubleshoot Firefox crashes (closing or quitting unexpectedly) article.

Er, no I couldn't. I can't enter -anything- in the Firefox address bar without causing an instant crash. I cannot, AFAIK, use ANY feature of Firefox at all.

If you can tell me a way to get at this info without using Firefox I'll do my best.

Start Firefox in Safe Mode {web link} While you are in safe mode;

Type about:preferences<Enter> in the address bar

Select Advanced > General. Look for and turn off Use Hardware Acceleration.

Poke around safe web sites. Are there any problems?

Then restart.

If you can't get Firefox to open, you will have to do this the hard way. Open the file browser / explorer on your computer. Enter this;

%APPDATA%\Mozilla\Firefox\Crash Reports\submitted

Copy the last 5-7 Recent File Names in the folder, including the date and time created. Post all the information in the reply box below.

Thanks, that I can do. Here are the last 7 crash IDs, times below (there doesn't seem to be a way to copy those).

bp-ffdca9a7-22d9-4d41-9590-440c92140928 bp-edde5f2f-aa43-46bc-89ce-c006c2140928 bp-58302b45-0b4a-42b2-8121-7a9eb2140928 bp-90401f5b-dd11-44b9-8ad8-ca1832140928 bp-d7d921a4-a3de-47a6-a4cb-ee6962140928 bp-2f5dae2f-9f58-45e2-86de-16f232140928 bp-ec8b758a-4f59-4ee3-89c2-a485b2140928

All dated 28/09/2014. Times, from the top down, are 19:12 18:56 18:53 18:44 18:32 18:28 18:26

Your crash reports all talk about; DWrite.dll

One source I looked at said; If you got dwrite.dll error then There is a 94% chance that your computer has registry problems.

DWrite sounds like "Direct Write" so I agree with Fred's suggestion about disabling hardware acceleration to work around a possible incompatibility with your graphics card driver software.

Can you start Firefox in Safe Mode by holding down the Shift key when starting Firefox (then choosing "Start in Safe Mode" when given the option)? If so, can you switch off hardware acceleration here:

"3-bar" menu button (or Tools menu) > Options > Advanced

On the "General" mini-tab, uncheck the box for "Use hardware acceleration when available"

This will take effect after you exit and start Firefox up again.

Did you try to disable hardware acceleration?

• https://support.mozilla.org/kb/upgrade-graphics-drivers-use-hardware-acceleration

On Windows, hold down the Shift key while starting Firefox with a double-click on the Firefox desktop shortcut to start Firefox in Safe Mode.

• https://support.mozilla.org/kb/Safe+Mode

Starting Firefox while holding down the shift key produces a slight change in behaviour: Firefox opens and says it's having a problem restoring tabs (as happens about half the time) I click on the close button, Firefox freezes then there is a slightly longer pause than usual before I get the crash screen. Here is the resulting crash report: bp-5bb42a48-096f-4c9e-bbbb-4291e2140929 dated 29/09/2014 at 01:28

I cannot follow the instructions to disable hardware acceleration. I cannot follow any instructions that require me to do anything in a firefox menu, because clicking on any menu causes a crash.

I don't quite see how a driver issue could be the underlying problem, as I have not changed my drivers in the last several months and there have been no issues until today.

Registry problems sound more like a possibility. I will see what Microsoft support has to say about them.

Create a new profile as a test to check if your current profile is causing the problem.

See "Creating a profile":

• https://support.mozilla.org/kb/profile-manager-create-and-remove-firefox-profiles
• http://kb.mozillazine.org/Standard_diagnostic_-_Firefox#Profile_issues

If the new profile works then you can transfer files from a previously used profile to the new profile, but be cautious not to copy corrupted files to avoid carrying over problems.

• http://kb.mozillazine.org/Transferring_data_to_a_new_profile_-_Firefox

Do a malware check with several malware scanning programs on the Windows computer. Please scan with all programs because each program detects different malware. All these programs have free versions.

Make sure that you update each program to get the latest version of their databases before doing a scan.

• Malwarebytes' Anti-Malware:
  http://www.malwarebytes.org/mbam.php
• AdwCleaner:
  http://www.bleepingcomputer.com/download/adwcleaner/
  http://www.softpedia.com/get/Antivirus/Removal-Tools/AdwCleaner.shtml
• SuperAntispyware:
  http://www.superantispyware.com/
• Microsoft Safety Scanner:
  http://www.microsoft.com/security/scanner/en-us/default.aspx
• Windows Defender:
  http://windows.microsoft.com/en-us/windows/using-defender
• Spybot Search & Destroy:
  http://www.safer-networking.org/en/index.html
• Kasperky Free Security Scan:
  http://www.kaspersky.com/security-scan

You can also do a check for a rootkit infection with TDSSKiller.

• Anti-rootkit utility TDSSKiller:
  http://support.kaspersky.com/5350?el=88446

See also:

• "Spyware on Windows": http://kb.mozillazine.org/Popups_not_blocked
• https://support.mozilla.org/kb/troubleshoot-firefox-issues-caused-malware

I cannot create a new profile. As I said in the OP, if I try to use the profile manager that also crashes.

I'm working my way through the malware scans, won't finish tonight. No actual malware found yet.

Check your anti-virus for a registry cleaner.

MacAfee does not have a registry cleaner feature.

I searched Microsoft support for entries under registry problems and cleaners. All the articles I found related to earlier versions of windows. It seems that windows 7 has an automatic feature which checks the registry daily and repairs it at need from earlier versions.

I cannot run Windows defender. I get a message saying that 'windows cannot access the file, I may not have the appropriate permissions to access it' - although my account is an administrator. I've seen a similar message before while investigating another issue and asked about it on the microsoft support forums, never got an answer.

Hi MadLogician, when I look at that last crash report more closely, it seems to relate to a problem with a font. By default, Firefox uses standard system fonts such as Times New Roman, Arial, and Courier New for content, and the fonts specified in your Windows theme/personalization settings for menu, dialog and toolbar text.

You can check for possible corrupted fonts using the procedures in the top answer in this thread: http://answers.microsoft.com/en-us/windows/forum/windows_7-desktop/how-do-i-fix-corrupted-font-files-in-windows-7/7860617d-e4a8-4792-a84b-b83f4bfd81b4

Thanks for this suggestion.

I haven't ever consciously installed any fonts, but it's possible that some game has installed some as part of the package or an existing font has become corrupted. As always, it's not clear why a system-wide problem would affect Firefox but not IE or Chrome.

Restoring default fonts does not fix the problem.

I'll try SFC and report back.

OK, I am not at all impressed with the Kaspersy software. I ran a quick scan, and after a few minutes it came up with a report saying 13 problems found. When I asked for details it produced a screen offering to sell me various versions of their paid software which could fix these problems. Also, this screen was presented as a web page in my default browser - not good when I am using their software to fix problems with my browser itself.

Why is Mozilla recommending software that uses this sort of bait-and-switch?

There was a button for 'how to fix your problems manually' but trying to load that page just crashed my IE browser.

I also found I was having some bizarre browser issues. I was trying to pay by paypal and it informed me that my browser was set not to accept cookies, which was nonsense. I uninstalled the Kaspersky software and the problem went away. Why would a product that's supposed to be purely a scanner interfere with cookies?

Hi MadLogician, Kaspersky products are generally compatible with Firefox, but one feature definitely can create issues: Kaspersky includes a feature to filter your browser connections. With secure sites this can lead to complications. You can turn off SSL scanning in Kaspersky's option if you decide to reinstall it.