This article describes how to troubleshoot problems connecting to websites that start immediately after updating Firefox to a new version. * Follow the instructions in this article if you can connect to websites using another browser (such as {for win}Internet Explorer{/for}{for mac}Safari{/for}{for linux}Epiphany{/for}), but not in Firefox. If no browsers can load websites, see [[No programs can load websites]]. * For troubleshooting connection problems unrelated to updating Firefox, see [[Firefox cannot load websites but other programs can]]. __TOC__ = The cause = If you were able to load websites until you updated Firefox, your Internet security software (including firewalls, antivirus programs, anti-spyware programs, and more) is likely preventing Firefox from connecting to the Internet. This problem occurs when your Internet security program was set to trust the previous version of Firefox, but no longer recognizes your updated version as trusted. '''Some Internet security programs can block Internet access even when they are in a "disabled" state.''' = Fixing the problem = To allow Firefox to connect to the Internet again: # Make sure your Internet security software is up-to-date (i.e. you are running the latest version). # Remove Firefox from your program's list of trusted or recognized programs, then add it back. If the Internet security program or firewall you are using is listed below, click its link to see a tutorial on how to configure it to allow Firefox to connect to the Internet again: * [[Configuring AVG Internet Security|AVG Internet Security]] * [http://www.avira.com/en/support-for-home-knowledgebase-detail/kbid/567 Avira Premium Security Suite (Avira Knowledge Base)] * [[Configuring BitDefender Internet Security|BitDefender Internet Security]] * [[Configuring CA Internet Security Suite|CA Internet Security Suite]] * [[Configuring Comodo Internet Security|Comodo Internet Security]] * [[Configuring Comodo Firewall Pro|Comodo Firewall Pro]] * [[Configuring F-Secure Internet Security|F-Secure Internet Security]] * [[Configuring Kaspersky Internet Security|Kaspersky Internet Security]] * [[Configuring McAfee Internet Security|McAfee Internet Security 2009 or 2010]] * [[Configuring McAfee Security Center|McAfee Security Center]] (McAfee Total Protection, McAfee AntiVirus, or McAfee Internet Security 2011) * [[Configuring Norton 360|Norton 360]] * [[Configuring Norton Internet Security|Norton Internet Security]] * [[Configuring Online Armor Free|Online Armor Free]] * [[Configuring Panda Internet Security|Panda Internet Security]] * [[Configuring Trend Micro Internet Security|Trend Micro Internet Security]] * [[Configuring Windows Firewall|Windows Firewall]] * [[Configuring ZoneAlarm Free Firewall|ZoneAlarm Free Firewall]] <!-- When adding a firewall, remember to add it to https://support.mozilla.com/kb/Firewalls as well. -->

This article describes how to troubleshoot problems connecting to websites that start immediately after updating Firefox to a new version.

• Follow the instructions in this article if you can connect to websites using another browser (such as Internet ExplorerSafariEpiphany), but not in Firefox. If no browsers can load websites, see Firefox and other browsers can't load websites.
• For troubleshooting connection problems unrelated to updating Firefox, see Firefox can't load websites but other browsers can.

The cause

If you were able to load websites until you updated Firefox, your Internet security software (including firewalls, antivirus programs, anti-spyware programs, and more) is likely preventing Firefox from connecting to the Internet.

This problem occurs when your Internet security program was set to trust the previous version of Firefox, but no longer recognizes your updated version as trusted.

Some Internet security programs can block Internet access even when they are in a "disabled" state.

Fixing the problem

To allow Firefox to connect to the Internet again:

1. Make sure your Internet security software is up-to-date (i.e. you are running the latest version).
2. Remove Firefox from your program's list of trusted or recognized programs, then add it back.

If the Internet security program or firewall you are using is listed below, click its link to see a tutorial on how to configure it to allow Firefox to connect to the Internet again:

• AVG Internet Security
• Avira Premium Security Suite (Avira Knowledge Base)
• BitDefender Internet Security
• CA Internet Security Suite
• Comodo Internet Security
• Comodo Firewall Pro
• F-Secure Internet Security
• Kaspersky Internet Security
• McAfee Internet Security 2009 or 2010
• McAfee Security Center (McAfee Total Protection, McAfee AntiVirus, or McAfee Internet Security 2011)
• Norton 360
• Norton Internet Security
• Online Armor Free
• Panda Internet Security
• Trend Micro Internet Security
• Windows Firewall
• ZoneAlarm Free Firewall