This article describes some causes and steps to take when Firefox takes a long time to start up. *If Firefox does not start up at all, see [[Firefox will not start]]. __TOC__ {for win, fx35} = Update Firefox = Firefox 3.5 may take an abnormally long amount of time to start after turning on your computer (this is known as a "cold start"). Thus is caused by a bug which was '''fixed in Firefox 3.5.1'''. Updating Firefox will fix the problem. # 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]]. {/for} = Change the home page = Problems with a website can cause Firefox to take a long time to start. Try changing your Firefox home page to a different website or use a blank home page. See [[How to set the home page]] for instructions. <!-- https://support.mozilla.com/questions/776797 and https://blog.mozilla.com/tglek/2010/10/04/diagnosing-slow-startup --> = Check your 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. If the problem began after installing, updating, or reconfiguring your antivirus software, contact the software provider for assistance. <!-- https://blog.mozilla.com/tglek/2010/10/04/diagnosing-slow-startup --> = Troubleshoot extensions or themes = Firefox loads extensions when it starts up and many extensions add startup tasks. See [[Troubleshooting extensions and themes]] for steps on how to identify an extension that may be causing the problem. = Other solutions = If the previous suggestions don't significantly reduce Firefox startup time, see [[Basic troubleshooting]] for other steps you can take to resolve the problem.

This article describes some causes and steps to take when Firefox takes a long time to start up.

• If Firefox does not start up at all, see Firefox won't start - find solutions.

Change the home page

Problems with a website can cause Firefox to take a long time to start. Try changing your Firefox home page to a different website or use a blank home page. See How to set the home page for instructions.

Check your 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. If the problem began after installing, updating, or reconfiguring your antivirus software, contact the software provider for assistance.

Troubleshoot extensions or themes

Firefox loads extensions when it starts up and many extensions add startup tasks. See Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems for steps on how to identify an extension that may be causing the problem.

Other solutions

If the previous suggestions don't significantly reduce Firefox startup time, see Basic troubleshooting for other steps you can take to resolve the problem.