This can be caused by a problem with an add-on. To see if this is the case follow the procedure in the [[troubleshooting extensions and themes]] article.

In the past, some versions of AVG Safe Search have caused that problem. You have a more current version of AVG Safe Search but there could be a reversion in the current AVG Safe Search causing the problem. Try disabling AVG Safe Search (Tools > Add-ons > Extensions, click on AVG Safe Search > click Disable) then exit Firefox, wait a few seconds, start Firefox and test to see if the problem is resolved. ----------------------------- <br /> The information submitted with your question indicates that you have out of date plugins with known security and stability issues that should be updated. To see the plugins submitted with your question, click "More system details..." to the right of your original question post. *Shockwave Flash 10.0 r32 *Next Generation Java Plug-in 1.6.0_21 for Mozilla browsers #'''Check your plugin versions''': http://www.mozilla.com/en-US/plugincheck/ #*'''Note: plugin check page does not have information on all plugin versions''' #Update the [[Managing the Flash plugin|Flash]] plugin to the latest version. #*http://www.adobe.com/software/flash/about/ #Update the [[Java]] plugin to the latest version. #*http://java.sun.com/javase/downloads/index.jsp (Java Platform: Download JRE)