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computer slow and seizing up

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I am having problems with Firefox seizing up on the computer. It totally seizes and nothing works in Firefox, other programmes being used at the same time do work normally even though Firefox has seized. One of the first signs this has happened is drop-down menus don't work. Clicking on the white cross in the top right hand corner of the screen does nothing and all I get is a bleeping sound when I do this.The only way to reboot it is to go to task manager to shut down then reload the programme. The computer then seizes again after a short while. I am using windows 8.1 64bit on two computers and both seize up. On the laptop I am using windows 7 32bit and I don't get any problems with Firefox. I have tried deleting Firefox then reinstalling a new download but still the same problem arises. It has got so bad that I have had to stop using Firefox on the two windows 8.1 64bit computers and am now using Internet Explorer and I don't get the issue of seizing up. The laptop with windows 7 32bit works perfectly well with Firefox. One thing I did notice in task manager is the memory usage is showing as about 500Mb and the CPU is almost at 100%. This has only just started to happen in the last 2-3 weeks. It is a shame because I like Firefox and the add-ons, can anyone help.

I am having problems with Firefox seizing up on the computer. It totally seizes and nothing works in Firefox, other programmes being used at the same time do work normally even though Firefox has seized. One of the first signs this has happened is drop-down menus don't work. Clicking on the white cross in the top right hand corner of the screen does nothing and all I get is a bleeping sound when I do this.The only way to reboot it is to go to task manager to shut down then reload the programme. The computer then seizes again after a short while. I am using windows 8.1 64bit on two computers and both seize up. On the laptop I am using windows 7 32bit and I don't get any problems with Firefox. I have tried deleting Firefox then reinstalling a new download but still the same problem arises. It has got so bad that I have had to stop using Firefox on the two windows 8.1 64bit computers and am now using Internet Explorer and I don't get the issue of seizing up. The laptop with windows 7 32bit works perfectly well with Firefox. One thing I did notice in task manager is the memory usage is showing as about 500Mb and the CPU is almost at 100%. This has only just started to happen in the last 2-3 weeks. It is a shame because I like Firefox and the add-ons, can anyone help.

All Replies (6)

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This problem of freezing sometimes is called a "hang." Does anything in this article help: Firefox hangs or is not responding - How to fix.

As a diagnostic, with the understanding that you might not want to use this setting normally, could you set Flash to "click to play" so that it doesn't start up without your approval? This can help distinguish pages that choke Firefox and pages triggering a problem in the Flash plugin. Here's how:

Open the Add-ons page using either:

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

In the left column, click Plugins. Then on the right side, find "Shockwave Flash" and change it from "Always Activate" to "Ask to Activate". When you load pages that want to use Flash, you should get a notification in one or more of these places:

  • video placeholders
  • infobar sliding down between the toolbar area and the page
  • "Lego-like" icon in the address bar

Notice any difference?

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Thanks for the reply, I tried what you said and it didn't work, after about an hour Firefox became unresponsive again same as before and I had to go into windows task bar to switch it off and reboot. There is a lot of of CPU usage when Firefox is on between 60-70% when I pulled up windows task bar and around 500M memory use, both which drop to very little when Firefox is ended.

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Could you try disabling nonessential extensions? That is, if you have extensions that you can live without for 24 hours, try disabling those temporarily on the Add-ons page. Either:

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

In the left column, click Extensions. Then you can disable the nonessential ones on the right side and try it out for a day to see whether it makes any difference.

Also, just as a footnote, 500MB of memory use is not that unusual and doesn't indicate a problem if you have a 4GB system.

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I have disabled all extensions that are not needed but nothing seems to work. An idea I had was that this problem started just after I downloaded and started to use Mozilla Thunderbird, which is a very good email programme. I turned off Thunderbird and used Firefox for most of the day with no problems, then I turned Thunderbird back on and the freezing up of Firefox started again. Have you heard of this before? I am having to use Internet Explorer with Mozilla Thunderbird at the moment and I get no problems with freezing. The system is 4GB memory so as you say should be able to handle Mozilla Firefox. Thank you for your help and advice Colin

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Hi Colin, what version of Thunderbird is it? There was just a major update (version 31.0) and this might be an issue with the new version that didn't occur with the previous release (24.6 / 24.7).

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Hi, the Thunderbird version is 24.6.0