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Why is Firefox constantly using 100% if ny processor time when I am using it?

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  • Last reply by cor-el

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When I use Firefox, I see that while I am browsing the internet, the CPU is running at 99% and Firefox is very sluggish. What is going on?

This happened

Every time Firefox opened

== A few days ago.

When I use Firefox, I see that while I am browsing the internet, the CPU is running at 99% and Firefox is very sluggish. What is going on? == This happened == Every time Firefox opened == A few days ago.

All Replies (1)

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Start Firefox in Diagnose Firefox issues using Troubleshoot Mode to check if one of your add-ons is causing your problem (switch to the DEFAULT theme: Tools > Add-ons > Themes). See Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems and Troubleshoot issues with plugins like Flash or Java to fix common Firefox problems

If it does work in Safe-mode then disable all your extensions and then try to find which is causing it by enabling one at a time until the problem reappears. You can use "Disable all add-ons" on the Safe mode start window. You have to close and restart Firefox after each change via "File > Exit" (on Mac: "Firefox > Quit") --- Your plugins list shows that you have the Mozilla ActiveX plugin installed. The Mozilla ActiveX plugin is not compatible with Firefox 2 and 3 and you should remove it. For instructions on how to remove the Mozilla ActiveX plugin see: http://kb.mozillazine.org/ActiveX

Your plugins list shows outdated plugin(s) with known security and stability risks.

# Java Plug-in 1.6.0_05 for Netscape Navigator (DLL Helper) 

Update the Java plugin to the latest version. See http://java.sun.com/javase/downloads/index.jsp#jdk (you need JRE)

You should also update the Adobe Reader. See Adobe Reader