Firefox warning message: Add-ons may be causing problems

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Firefox warning message: Add-ons may be causing problems

This article applies to:

Platform(s): Windows 7, Vista, Windows XP, Windows 2000, Windows 2003, Windows 2008 Server
Browser(s): Firefox
Java version(s): 6.0

SYMPTOMS

The following window appears while launching Firefox browser with the warning: 'Firefox has determined that the following add-ons are known to cause stability or security problems'.

screen shot 'Firefox has determined that the following add-ons are known to cause stability or security problems'

CAUSE

Older versions of the Java Deployment Toolkit (DT) are disabled by Firefox. Java versions prior to Java 6u20 may be affected.

SOLUTION

Update to Java 6 Update 20 and later versions, to resolve the issue in Firefox browsers.
If you see the warning message, follow these steps:

Click on Disable check box as shown in the screen shot.
Click on Restart Firefox.
Download the latest recommended Java version.

Note: If you do not see the warning message, update to the latest version of Java to avoid the warning message.

RELATED INFORMATION

Remove Older Versions of the Java Deployment Toolkit Plug-in
Listed below are alternative methods to remove the older version of the Java DT plug-in from your system, if you are not updating to the latest Java 6 version.

Method 1: Using Windows Search

Perform search on your computer for npdeploytk.dll file. (using Windows search)
Once this file is found, delete file.
Now restart Firefox browser and verify that, the Java DT plug-in prior to 6.0.200.2 is not listed in Firefox plug-in.

Method 2: Using Windows Explorer

Open Windows Explorer (for e.g. click on Start and then My computer).
Navigate to C: \Program Files\Java\jre6\bin\new_plugin.
Verify you find npdeploytk.dll file.
Delete this file.
Now restart Firefox browser and verify that, the Java DT plug-in prior to 6.0.200.2 is not listed in Firefox plug-in.

MORE TECHNICAL INFORMATION

Java Deployment Toolkit versions prior to 6.0.200.2 may be flagged by Firefox as 'Add-ons may be causing problems'. Refer to the Java Deployment Toolkit FAQ for more information.