#mozilla firefox errors

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.

Mozilla has released Firefox version 81.0.2 for various platforms. This release fixes an incompatibility issue with Twitter that led to the micro-blogging site not loading for several Firefox users. Loading Twitter on Firefox let to a blank or error page for users. Calling this a ‘known temporary issue,' Mozilla said that it has been fixed in the latest release (version 81.0.2) and that users should update in order to fix it. The update has reportedly rolled out to the stable channel for Android, Linux, macOS, and Windows.

Firefox version 81.0.2 has been first offered to release channel users. As per Mozilla's release notes, it has fixed an incompatibility issue with Twitter that was manifesting itself with the intermittent display of a network protocol violation error page. Fix Firefox Error

A lot of users opening Twitter on Firefox would see the following message: “The site at twitter experienced a network protocol violation that cannot be repaired" error. "The page you are trying to view cannot be shown because an error in the data transmission was detected. Please contact the website owners to inform them of this problem.”

Several users had raised the issue with Firefox, some of them ironically on Twitter. Mozilla had offered a temporary workaround for the issue, and is suggesting that users should try it if they are unable to update to version 81.0.2 that fixes the issue.

How to update Firefox on desktop

You can update to Firefox's latest version by clicking on the menu, then Help, and select About Firefox. In this window, Firefox will check for updates and download them automatically. Restart Firefox then, to update the browser.

Mozilla published a support document with a quick fix for a widely reported known issue causing Twitter not to load on the Firefox web browser.

According to a bug Mozilla has been tracking and working on fixing for the last 20 days, some users might see blank pages or errors when trying to visit the social network's website, with some reports also saying that the issue also affects mobile users. Fix Firefox Error

"The page you are trying to view cannot be shown because an error in the data transmission was detected," the error adds. "Please contact the website owners to inform them of this problem."

While Mozilla hasn't shared the Firefox versions affected by this problem, affected users say [1, 2] that the loading errors have started to appear on both mobile and desktop devices after updating to Firefox 81.0 last month.

How to fix Twitter not loading on Firefox

"There is a known temporary issue on Firefox that causes a blank or error page when loading Twitter," Mozilla explains in the support document published earlier. "We are working hard to come up with a fix."

Until Mozilla's engineers manage to fix this known issue, you can follow this procedure to get rid of the errors and blank pages showing up when trying to open Twitter:

Enter about:serviceworkers in the address bar (as shown in the screenshot embedded below)

Look for Twitter on the list then click its Unregister button.

Twitter should load the next time you visit it.

Reports are also saying that hard reloading Twitter's site using CTRL+F5 will also temporarily allow you to open Twitter pages.

Additionally, going to about:config and disabling dom.serviceWorkers.enabled will also remove the network violation errors.

Sometimes, the video or audio content in a web page cannot be properly downloaded and displayed in Firefox. This article will help you solve these problems.

Allow autoplay of media with sound

Firefox may be blocking media with sound from playing automatically. To allow media autoplay, see Allow or block media autoplay in Firefox.

HTML5 audio and video

Firefox has built in support for open media formats usually associated with MP3, WebM, Ogg and Wave containers. However, MP4 containers usually depend on platform decoders for AAC and H.264 audio and video streams. For more information, see Fix video and audio playback problems on Firefox for Windows and HTML5 audio and video in Firefox.

Disable interfering extensions or ad-blocking software

Ad-blocking software, such as anti-banner filters of your Internet Security program, or extensions, such as Flashblock or Adblock Plus, can prevent audio or video content from playing.

If the site works with ad-blocking disabled, you may want to add the site to your whitelist in your adblocker filter.

If the video or audio plays when you disable all extensions, then one of your extensions was causing the problem. For more information, see Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems.

Check some Firefox settings

Cookies:

Click the menu button and select Options.

Select the Privacy & Security panel and go to the Cookies and Site Data section.

Verify that cookies are enabled and that the site is not blocked in the Exceptions list.

History:

Click the menu button and select Options.

Select the Privacy & Security panel and go to the History section.

Make sure that Firefox is set to Remember history.

Pop-up windows:

Click the menu button and select Options.

Select the Privacy & Security panel and go to the Permissions section.

Allow the website as an exception to the "Block pop-up windows" setting.

Reset preferences

See Reset Firefox preferences to troubleshoot and fix problems.

Remove specific entries in the hosts file (advanced users)

If you use a hosts file, you can temporarily disable it by renaming it Xhosts. Or, you can edit the hosts file to remove specific entries such as ad.doubleclick.net that can cause videos on certain sites to fail (for more information, see this MozillaZine forum thread). To apply changes to your hosts file, you may need to flush the DNS cache by entering the command: ipconfig /flushdns in the Run dialog box on Windows.

The PR_CONNECT_RESET_ERROR issue is encountered when the user tries to use Mozilla Firefox to connect to a website server with the HTTPS protocol but the request gets denied. This error message essentially means that the peer or some middlebox in between (most likely a firewall) is terminating the connection forcibly.

As it turns out, TCP protocol filtering can be responsible for interrupting the connection between the end-user (you) and the webserver you’re attempting to access due to a false positive. In this case, you should be able to fix the issue by accessing the advanced settings of your AV and disabling protocol filtering. ESET AV is known to have this feature enabled by default. Fix Firefox Error

The issue may also be caused by certain temporary files which can interfere with new webserver connections. This typically happens if the user tries to access the same website with both a regular connection and one filtered through a VPN / Proxy. In this case, you can fix the issue by clearing your browser cache.

An overprotective firewall can also be responsible for the interruption between the end-user and the webserver. A false positive can be responsible for this behavior. If this scenario is applicable, you can fix the problem by uninstalling the 3rd party firewall and reverting back to the default Windows firewall.

Certain websites take security precautions against end-users that filter their connection through a VPN or proxy. It’s possible that you’re encountering this issue due to the fact that you’re using a VPN or proxy. In this case, you can fix the issue by disabling the proxy server or uninstalling the VPN client.

Depending on your ISP, there’s also a chance that you’re seeing this Firefox error due to a geo lock that is preventing you from accessing some web-servers from certain locations. In this case, you can change your location via a VPN tool in order to access the website.

This issue is quite common among users that are attempting to access certain web servers from a university or work environment. Some restricted networks such as these will block users from accessing certain websites. Brave browser is a good alternative in this case.

Like every program, Firefox sometimes freezes and crashes, and some websites might not load correctly. These occasional glitches don't require your attention, but if the program repeatedly runs into a major problem, it might indicate trouble with your profile settings or an extension, or the program itself might need reinstalling. Full reinstallation is a last resort, however, and most solutions retain your browser customizations and bookmarks.

Initial Troubleshooting Steps

Before taking any elaborate measures, try rebooting your computer. Though a stereotypical answer to almost any computer problem, a reboot can actually fix all sorts of unusual problems by clearing everything out of the system's memory. If you're having trouble with a particular site, also try erasing your cache: Press "Ctrl-Shift-Del," set the time range to "Everything" and make sure "Cache" is checked in the Details section. Fix Firefox Error

If these basic solutions don't help, the next step is to determine whether the problem lies in your Firefox profile, which contains your add-ons and settings, or in the software installation itself. As a test, open Firefox in Safe Mode: In Firefox 29 and above, click "?" in the Firefox menu and pick "Restart with Add-Ons Disabled." If you can't open Firefox at all, hold "Shift" as soon as you double-click the program's icon. If Firefox works in Safe Mode, you probably have a profile problem or trouble with plugins; if it doesn't work, you might need to reinstall the software.

Profile Problems -- Test Your Add-Ons

Buggy extensions and themes are a common cause of Firefox troubles. Even if each extension you use works independently, conflicts between extensions can lead to hard-to-diagnose issues. Assuming you can open Firefox, the first step to a fix is figuring out which, if any, of your add-ons is to blame.

If you recently added a new add-on, try disabling it first -- open the Firefox menu, click "Add-Ons," open either the "Extensions" or "Appearance" tab and press "Disable" on the relevant item. Otherwise, narrow down the problem by disabling add-ons, restarting Firefox and testing for the problem. To save time, disable half of the add-ons at once. If the problem remains, disable the other half instead. Re-enable a few at a time until the problem occurs, indicating the culprit, which you can then remove or research for a specific solution.