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Firefox keeps crashing on startup, how can I fix it? I've already uninstalled it and reinstalled it, same problem.

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It doesn't even load the window. It just says that it crashed and gives me this:

Problem signature:

 Problem Event Name:	BEX
 Application Name:	firefox.exe
 Application Version:	31.0.0.5310
 Application Timestamp:	53c75e72
 Fault Module Name:	nsib.dll
 Fault Module Version:	5.1.3.1
 Fault Module Timestamp:	53f5c0ba
 Exception Offset:	00135fe0
 Exception Code:	c0000005
 Exception Data:	00000008
 OS Version:	6.1.7601.2.1.0.768.3
 Locale ID:	1033
 Additional Information 1:	0a9e
 Additional Information 2:	0a9e372d3b4ad19135b953a78882e789
 Additional Information 3:	0a9e
 Additional Information 4:	0a9e372d3b4ad19135b953a78882e789

Help

It doesn't even load the window. It just says that it crashed and gives me this: Problem signature: Problem Event Name: BEX Application Name: firefox.exe Application Version: 31.0.0.5310 Application Timestamp: 53c75e72 Fault Module Name: nsib.dll Fault Module Version: 5.1.3.1 Fault Module Timestamp: 53f5c0ba Exception Offset: 00135fe0 Exception Code: c0000005 Exception Data: 00000008 OS Version: 6.1.7601.2.1.0.768.3 Locale ID: 1033 Additional Information 1: 0a9e Additional Information 2: 0a9e372d3b4ad19135b953a78882e789 Additional Information 3: 0a9e Additional Information 4: 0a9e372d3b4ad19135b953a78882e789 Help

All Replies (1)

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A "BEX" error often indicates there is a malware process trying to inject itself into Firefox in an inappropriate way, so Windows shuts it down to protect you.

When I search for information on nsib.dll, it's inconclusive. For example: VirusTotal analysis.

Assuming it is a bad add-on, I suggest starting here:

Open the Windows Control Panel, Uninstall a Program. After the list loads, click the "Installed on" column heading to group the infections, I mean, additions, by date. This can help in smoking out undisclosed bundle items that snuck in with some software you agreed to install. Take out as much trash as possible here.

You can "mop up" remaining issues with the scanning/cleaning tools suggested in this support article: Troubleshoot Firefox issues caused by malware.

Finally, start Firefox in its Safe Mode by holding down the Shift key when double-clicking the Firefox shortcut/icon. In the small dialog that should appear, choose "Start in Safe Mode"

Then open the Add-ons page using either:

  • Ctrl+Shift+a
  • "3-bar" menu button (or Tools menu) > Add-ons

In the left column, click Extensions. Then, if in doubt, disable (or Remove, if possible) unrecognized and unwanted extensions.

Often a link will appear above at least one disabled extension to restart Firefox. You can complete your work on the tab and click one of the links as the last step.

Does that clear it up?