Firefox takes a long time to start up

If Firefox is taking an abnormally long amount of time to start after turning on your computer, it is because of a bug in Firefox 3.5, which was '''fixed in Firefox 3.5.1'''. # At the top of the Firefox window, click on the {menu Help} menu. # Select {menu Check for Updates...}. # Follow the instructions in the Firefox Update wizard. For more information, see [[Updating Firefox]]. <!-- This article describes some causes and steps to take when Firefox takes a long time to start up for the first time after turning on your computer. This is also known as a cold start. __TOC__ {for win} {for fx35} = Large numbers of Windows Temp Files and Internet Explorer Cache files = Firefox uses the contents of temporary folders to improve your browsing peformance. In Firefox 3.5 the number of files used was increased, if you have a large number of such files this can cause Firefox to be very slow to start up. This is being addressed for the next release of Firefox. In the meantime, you can take the following steps to clear out these temporary files: Thanks to Noah: http://support.mozilla.com/tiki-view_forum_thread.php?locale=en-US&comments_parentId=381674&forumId=1 see also bug 501605 # Clear out the cached files in Internet Properties ## From the Start menu, select {button Control Panel}, then {filepath Network & Internet Connections}, then {filepath Internet Options} ## On the General tab, click {button Delete} under Browsing History ## Click the {button Delete files...} button under Temporary Internet Files and confirm. # Delete all files and subfolders in the following folders (you may need to [http://www.bleepingcomputer.com/tutorials/tutorial62.html show hidden folders] to see and delete some files or folders). ** {filepath C:\Documents and Settings\<username>\Local Settings\Temp} (Windows XP) ** {filepath C:\Users\<username>\AppData\Local\Temp} (Windows Vista) ** {filepath C:\Users\<username>\AppData\Local\Microsoft\Windows\Temporary Internet Files\Content.IE5} (Windows Vista) *** This folder doesn't show up even when showing hidden folders; you need to type the full path into a Windows Explorer window to access the folder so you can empty it. # Empty the Recycle Bin # Windows Vista users can also use the [http://windowshelp.microsoft.com/Windows/en-US/Help/1264bc24-72a8-48aa-84e3-a355327139d91033.mspx Disk Cleanup Utility] to remove unneeded files. If this problem returns frequently, you can lower the amount of space used for the IE cache (and have it clear automatically) by changing internet options: # From the Start menu, select {button Control Panel}, then {filepath Network & Internet Connections}, then {filepath Internet Options} # On the General tab, click {button Settings} under '''Temporary Internet Files''' # Change the '''Amount of disk space to use''' to a lower number such as 100 # Click {button OK} {/for} {/for} = Antivirus software = Firefox reads a number of files normally during startup. Some antivirus software may do intensive scans of each of these files during startup and block access until those scans complete. = Large numbers of fonts = Firefox loads all your fonts so that it can allow websites to display pages in all available fonts. Having large numbers of fonts can slow down this process. Removing unused fonts can sometimes greatly speed up Firefox startup times. Bug 502821 = Extensions or themes = Firefox loads extensions when it starts up and many extensions themselves add startup tasks. See [[Troubleshooting extensions and themes]] for steps on how to identify the extension that may be causing the problem. = Other causes = [[Basic troubleshooting]] steps can help diagnose and isolate the cause of this issue if the above steps don't help. -->

If Firefox is taking an abnormally long amount of time to start after turning on your computer, it is because of a bug in Firefox 3.5, which was fixed in Firefox 3.5.1.

1. At the top of the Firefox window, click on the Help menu.
2. Select Check for Updates....
3. Follow the instructions in the Firefox Update wizard. For more information, see Update Firefox to the latest release.