#fix firefox error

After the update to Firefox 63, Windows users with Quick Heal security software might be impacted by tabs repeatedly crashing while using 32-bit versions of Firefox. Fix Firefox Error

We are in contact with the vendor about this problem. While they are looking into deploying a fix for this, a workaround for affected users is to disable the Browser Sandbox feature within Quick Heal:

Open your Quick Heal security product

On the Dashboard, click on Internet & Network

Disable the Browser Sandbox setting by clicking the toggle next to it, so that it’s OFF:

Restart Firefox for the change to take effect

This article describes what to do if you get a tab named "Firefox Updated" or see the message "You've been updated to the latest version of Firefox." every time you start Firefox even if you haven't updated Firefox.

There are two possible causes for this. You may have that tab saved accidentally as your home page (which Firefox opens each time you start) or Firefox may be having trouble saving to your settings file which results in it not realizing you have already seen the "You've been updated" message.

"Firefox Updated" tab saved to your home page

Click the menu button 📷 and select Options.

Select the General panel.

Highlight the text in the text field in the Home page area.

If it includes something similar to http://www.mozilla.com/en-US/firefox/4.0/whatsnew/ then you have accidentally added the "Firefox Updated" page to the sites that Firefox loads on startup.

You can fix this by clicking Restore to Default. To change your home page to something else, see the How to set the home page article.

Firefox is unable to save your preferences

Firefox changes a setting in its preferences file to determine whether you've seen the "Firefox Updated" tab. If you are having problems with that file then Firefox will be unable to save this information and will show you the "Firefox Updated" tab each time you start it. You may also notice that options you select in your Options tab are not kept after you close Firefox. To correct this, use the steps outlined in the How to fix preferences that won't save article.

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 Explorer), 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.

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. For detailed instructions, see Configure firewalls so that Firefox can access the Internet.

Firefox may display a TLS connection error when your antivirus software prevents data from being sent to your browser. This happens when your antivirus software fails to register itself with Firefox as a valid issuer of TLS certificates. Fix Firefox Error

Mozilla has added an Enterprise Roots preference to Firefox as a solution to the problem. This preference can be used to import any root certificate authorities (CAs) that have been added to the operating system, to resolve your TLS connection error. You can determine if a website is relying on an imported root certificate by clicking the Site Information icon in the address bar.

Starting with Firefox version 68, when a TLS connection error occurs Firefox will automatically enable the Enterprise Roots preference and attempts to connect again. If the issue is resolved, then the Enterprise Roots preference remains enabled. However, you may want to disable this behavior, so this article explains how to do just that without compromising security.

You can modify this behavior and prevent Firefox from automatically enabling the import of CAs that have been added to the operating system when a TLS connection error occurs, as follows:

Type about:config in the address bar and press Enter. A warning page may appear. Click Accept the Risk and Continue to go to the about:config page.

Type enterprise in the Search field.

Click the Toggle button next to the preference security.certerrors.mitm.auto_enable_enterprise_roots to change its value from true to false.

To prevent CAs that have been added to the operating system from being automatically imported each time Firefox restarts:

In the about:config page, search for enterprise as explained above.

Click the Toggle button next to the preference security.enterprise_roots.enabled to change its value from true to false.

Resetting preferences (zoom, tabs, privacy, network, encryption, updates, where to save file downloads, etc.) is one of many procedures that can be helpful in troubleshooting Firefox problems. We'll explain two ways to do this.

If changes to preference settings are not saved when you restart Firefox, see How to fix preferences that won't save.

Solution 1: Refresh Firefox

The refresh feature restores Firefox to its default state while saving your essential information. This solution will reset preferences but will also remove other customizations, including added extensions and themes. For more information, see Refresh Firefox - reset add-ons and settings.

Click the menu button click Help and select Troubleshooting Information. The Troubleshooting Information tab will open.

Under the Application Basics section next to Profile Folder, click Open Folder. Your profile folder will open.

Click the Firefox menu and select Exit.

Locate and delete the file prefs.js (or rename it, for example, to prefs.jsOLD, to keep the old file as a backup). If you find more than one, a prefs.js.moztmp file or a user.js file, delete (or rename) these as well.

You can close the profile folder and open Firefox now.

If you see a "Profile Missing" error message that says, Your Firefox profile cannot be loaded. It may be missing or inaccessible it usually means that Firefox can't find or access the profile folder. This article explains what to do if you see this error.

If you moved, renamed, or deleted your Firefox profile folder

Firefox stores your user data and settings in a special profile folder and pulls information from this folder every time you start Firefox. The default profile folder location is under the %APPDATA%\Mozilla\Firefox\Profiles folder, which you can find using these instructions. Fix Firefox Error

Profile was moved or renamed

If you know where your profile is, try one of the following methods to help Firefox find it.

Move the profile folder back to its original location.

Restore the profile's original name if you've changed it.

Create a new profile using the Profile Manager using the instructions to start the Profile Manager when Firefox is closed. Give it a descriptive name, click on the Choose Folder button, and then select the profile folder you moved or renamed, before you finish the Create a new profile wizard.

Profile was deleted

If you deleted or lost your profile folder and have no way of restoring it, use one of these methods to create a new Firefox profile:

Method 1: Use the Profile Manager wizard

Follow the steps in the Profile Manager - Create, remove, or switch Firefox profiles article to create a new profile.

Method 2: Manually delete the profiles.ini file

If you have problems accessing the Profile Manager, you can create a new default Firefox profile by deleting the profiles.ini file, using these steps:

This article describes what to do when searches from Firefox don't go to the expected site(s). For example, Google searches may redirect to a page with a lot of advertising or using a different search engine.

Only address bar searches are affected

If a term is entered in the address bar, Firefox sends a request to your Internet provider to see if the term is actually a website address. If it isn't, Firefox will then do a search using your default search engine (for more information, see Search with the Firefox address bar). A number of Internet providers, however, will redirect you to their own search site instead. Fix Firefox Error

Some service providers offer "DNS Assistance" which is what is doing the redirecting. Check with your provider to see if you can opt out of this service.

If you are unable to opt out from your service provider, the following workarounds may help you retain the ability to search from the location bar:

Only do multi-word searches from the Location bar. If you put multiple words in your search terms, Firefox will start with a Location bar search. You can often use a dummy word that is ignored by the search engine (such as the + character). For example, you will need to type + searchterm when the search term is one word (that space is important) but only search terms when the search terms are multiple words.

You can set up a smart keyword that corresponds to the search and prepend your search with this keyword. For example, you can use the keyword g to search Google. From then on, you would just have to type g searchterm to perform a search from the location bar. For instructions on how to set up smart keywords, see How to search IMDB, Wikipedia and more from the address bar.

If you have a router, ask your ISP about changing your DNS server.

All searches are affected

If searching using the search bar and searching directly from the site itself are both being redirected to alternate sites, it is likely that this redirection is being caused by malicious software such as a virus, spyware or trojan installed on your computer. See Troubleshoot Firefox issues caused by malware for instructions to get rid of malware.

Technology is wonderful, but sometimes it doesn’t work quite as we’d expect. Imagine you’re hard at work online. Suddenly, you’re presented with a security warning and the scary-looking message PR_END_OF_FILE_ERROR. This would be a little alarming to most users. Fix Firefox Error

In reality, this semi-common error with the Firefox browser is usually not warning you about an actual security threat. Instead, it tends to be caused by issues with the browser itself. In this article, we’ll walk you through what the error means, what might be causing it, and how to fix it.

First, some background. A cipher suite is an algorithm or set of instructions used to secure a network connection over the Secure Sockets Layer (SSL) or Transport Layer Security (TLS) protocol. Your browser has a list of cipher suites it can use to try to connect to a website secured with SSL or TLS. It will run down this list and try each cipher until it’s able to connect. If it can’t, you get a secure connection error.

PR_END_OF_FILE_ERROR is a secure connection error that occurs in the Firefox browser. It happens when Firefox isn’t able to establish a secure connection to a site due to the browser’s “cipher suites” failing. In other words, it’s reached the end of the file containing the cipher suites and none have worked (hence the error name). While it doesn’t appear all the time, it generally affects all sites the user tries to visit when it shows up.

Normally a secure connection error would be cause for concern, but in the case of the PR_END_OF_FILE_ERROR, the problem actually lies with the configuration of either the browser or some third-party service that’s coming in between the browser and the site, rather than a genuine security issue.

Causes of the PR_END_OF_FILE_ERROR

There are a number of potential causes for this browser error, but most of the time it’s one of four unrelated things:

Virtual Private Network (VPN) or proxy connections. If you’re using a VPN or proxy to browse the web anonymously, it could be the cause of this error. These types of services intercept your connection and function as a kind of middle-man between the browser and the site you’re visiting, but they don’t always work perfectly.

Incorrect cipher variants. It’s possible that the cipher variants Firefox is using are not supported by either the browser itself or by the site you’re trying to visit. This is most likely to happen if you’ve tried to modify your browser’s SSL settings.

A corrupted Firefox browser profile. A relatively common cause of this error is a corrupted Firefox profile. There are a number of reasons why your profile might have become corrupted, but one of the more common ones seems to be Firefox Sync issues between the desktop browser and the mobile version.

Third-party security software. Security suites like Avast, Kaspersky, and BitDefender can sometimes be overly aggressive about blocking traffic. While these antivirus programs can do a lot to keep your computer safe, they’re also a frequent cause of seemingly random problems like this.