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Firefox takes up all the CPU and downloads like crazy.

  • 6 replies
  • 2 have this problem
  • 3 views
  • Last reply by mgwmgw

Firefox is taking up a lot of CPU and apparently downloading something like crazy. I kill the process, restart, and it happens again.

I initially blamed my ISP but when I switched to Chrome the problems went completely away.

Firefox is taking up a lot of CPU and apparently downloading something like crazy. I kill the process, restart, and it happens again. I initially blamed my ISP but when I switched to Chrome the problems went completely away.

Chosen solution

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

See "Basic Troubleshooting: Make a new profile":

There may be extensions and plugins installed by default in a new profile, so check that in "Tools > Add-ons > Extensions & Plugins" in case there are still problems.

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

See:


Do a malware check with some malware scanning programs on the Windows computer.
You need to scan with all programs because each program detects different malware.
Make sure that you update each program to get the latest version of their databases before doing a scan.

You can also do a check for a rootkit infection with TDSSKiller.

See also:

Read this answer in context 👍 0

All Replies (6)

By changing my home page from linkedin to google, I seem to have gotten in working enough to get the trouble shooting information:


 Application Basics
       Name
       Firefox
       Version
       11.0
       User Agent
       Mozilla/5.0 (Macintosh; Intel Mac OS X 10.6; rv:11.0) Gecko/20100101 Firefox/11.0
       Profile Directory
         Show in Finder
       Enabled Plugins
         about:plugins
       Build Configuration
         about:buildconfig
       Crash Reports
         about:crashes
       Memory Use
         about:memory
 Extensions
       Name
       Version
       Enabled
       ID
       Adblock Plus
       2.0.3
       true
       {d10d0bf8-f5b5-c8b4-a8b2-2b9879e08c5d}
       Add to Amazon Wish List Button
       1.8
       true
       amznUWL2@amazon.com
       AddThis
       3.5.7
       true
       {3e0e7d2a-070f-4a47-b019-91fe5385ba79}
       Firebug
       1.9.1
       true
       firebug@software.joehewitt.com
       LinkedIn Companion for Firefox
       3.5.1
       true
       {e2337727-f9c9-411b-929e-287584341d1a}
       Password Reuse Visualizer
       0.12
       true
       jid1-bOHVlh4oBvBc7A@jetpack
       StumbleUpon
       3.99
       true
       {AE93811A-5C9A-4d34-8462-F7B864FC4696}
       Xmarks
       4.0.5
       true
       foxmarks@kei.com
 Modified Preferences
     Name
     Value
       accessibility.typeaheadfind.flashBar
       0
       browser.history_expire_days.mirror
       99999
       browser.places.importBookmarksHTML
       false
       browser.places.importDefaults
       false
       browser.places.leftPaneFolderId
       -1
       browser.places.migratePostDataAnnotations
       false
       browser.places.smartBookmarksVersion
       2
       browser.places.updateRecentTagsUri
       false
       browser.startup.homepage
       http://world.std.com/~mgw/
       browser.startup.homepage_override.buildID
       20120312181643
       browser.startup.homepage_override.mstone
       rv:11.0
       browser.tabs.warnOnOpen
       false
       extensions.lastAppVersion
       11.0
       font.size.variable.x-western
       18
       general.autoScroll
       false
       network.cookie.prefsMigrated
       true
       places.database.lastMaintenance
       1333993096
       places.history.expiration.transient_current_max_pages
       53688
       places.history.expiration.transient_optimal_database_size
       85899344
       places.last_vacuum
       1299439220
       print.macosx.pagesetup-2
       PD94bWwgdmVyc2lvbj0iMS4wIiBlbmNvZGluZz0iVVRGLTgiPz4KPCFET0NUWVBFIHBsaXN0IFBVQkxJQyAiLS8vQXBwbGUvL0RURCBQTElTVCAxLjAvL0VO…
       print.print_bgcolor
       false
       print.print_bgimages
       false
       print.print_command
       print.print_downloadfonts
       true
       print.print_evenpages
       true
       print.print_in_color
       true
       print.print_margin_bottom
       0.5
       print.print_margin_left
       0.5
       print.print_margin_right
       0.5
       print.print_margin_top
       0.5
       print.print_oddpages
       true
       print.print_orientation
       0
       print.print_page_delay
       50
       print.print_pagedelay
       500
       print.print_paper_data
       0
       print.print_paper_height
       11.00
       print.print_paper_size
       262144
       print.print_paper_size_type
       1
       print.print_paper_size_unit
       0
       print.print_paper_width
       8.50
       print.print_printer
       print.print_reversed
       false
       print.print_scaling
       1.00
       print.print_shrink_to_fit
       true
       print.print_to_file
       false
       print.print_unwriteable_margin_bottom
       57
       print.print_unwriteable_margin_left
       25
       print.print_unwriteable_margin_right
       25
       print.print_unwriteable_margin_top
       10
       privacy.cpd.cache
       false
       privacy.cpd.downloads
       false
       privacy.cpd.formdata
       false
       privacy.cpd.history
       false
       privacy.cpd.sessions
       false
       privacy.sanitize.migrateFx3Prefs
       true
       privacy.sanitize.timeSpan
       0
       security.default_personal_cert
       Select Automatically
       security.warn_viewing_mixed
       false
 Graphics
       Vendor ID
       10de
       Device ID
       0407
       WebGL Renderer
       NVIDIA Corporation -- NVIDIA GeForce 8600M GT OpenGL Engine -- 2.1 NVIDIA-1.6.36
       GPU Accelerated Windows
       1/1 OpenGL
       AzureBackend
       skia

But it still froze up, just took a moment longer. Opening Firefox in safe mode seems to prevent the problem for the moment, which suggests that the plugin checker is telling me something is good when it is not.

You could try to uninstall and reinstall Firefox, and see if that helps. Maybe it's trying to download an update?? I'm not sure. But try that and if it persists, let us know.

Thanks for the suggestion. I did that. It didn't help. I tried disabling all add-ons and it is still frozen up. Freezing up just took a little longer.

Would there be a way that I could turn on some kind of extra logging so that we could diagnose what it is doing? I would be happy to FTP or email the logs to somewhere useful if they are too big to post here.

Chosen Solution

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

See "Basic Troubleshooting: Make a new profile":

There may be extensions and plugins installed by default in a new profile, so check that in "Tools > Add-ons > Extensions & Plugins" in case there are still problems.

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

See:


Do a malware check with some malware scanning programs on the Windows computer.
You need to scan with all programs because each program detects different malware.
Make sure that you update each program to get the latest version of their databases before doing a scan.

You can also do a check for a rootkit infection with TDSSKiller.

See also:

Making a new profile seems to have solved the problem. Thanks much.