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firefox maxing my cpu and runs VERY slow i have reset firefox and re installed it, diddnt work

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  • 22 have this problem
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  • Last reply by poorloading

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firefox maxing my cpu and runs VERY slow i have reset firefox and re installed it, diddnt work i have googles searched about it and tryed so manny things to fix it but nothing works this is my last idea posting here

firefox maxing my cpu and runs VERY slow i have reset firefox and re installed it, diddnt work i have googles searched about it and tryed so manny things to fix it but nothing works this is my last idea posting here

All Replies (8)

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got this pc from a friend awhile ago and it use to run firefox perfect now it dont i dont know what he did or what but please help me fix it

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Did you do a clean reinstall and deleted the Firefox program folder?

  • (32 bit Windows) C:\Program Files\Mozilla Firefox\
  • (64 bit Windows) C:\Program Files (x86)\Mozilla Firefox\

Try to boot the computer in Windows Safe mode with network support (press F8 on the boot screen) as a test to see if that helps.

Create a new profile as a test to check if your current profile is causing the problems.

See "Creating a profile":

If the new profile works then you can transfer some files from an existing profile to the new profile, but be careful not to copy corrupted files.

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i have already done all that but just tryed it again and diddnt work i even deleted the old profile and made a new one after i fellow your steps and sorry for late reply got a little busy

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anything else to try?

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can anyone help me?

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A possible cause is security software (firewall,anti-virus) that blocks or restricts Firefox or the plugin-container process without informing you, possibly after detecting changes (update) to the Firefox program.

Remove all rules for Firefox and the plugin-container from the permissions list in the firewall and let your firewall ask again for permission to get full unrestricted access to internet for Firefox and the plugin-container process and the updater process.

See:

Try to boot the computer in Windows Safe mode with network support (press F8 on the boot screen) as a test to see if that helps.

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i use microsoft security essentials so it uses the windows firewall im sure cuz i dont see any firewall setting on it

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and i already took it off there and re put it back with no change