This article explains why you may see a Secure Connection Failed or a Did Not Connect: Potential Security Issue error page and what can you do.

• If you see a Your connection is not secure Warning: Potential Security Risk Ahead error page, see the What do the security warning codes mean? article.
• To troubleshoot other error messages, see Websites don"t load - troubleshoot and fix error messages .

Table of Contents

Secure connection cannot be established

Alternatively, you can uninstall third-party security software and use Microsoft Security Essentials , the free antivirus offered by Microsoft for Windows 7.Alternatively, you can uninstall third-party security software and use Windows Defender, the built-in antivirus on Windows 8 and Windows 10.

Incorrect system clock

Firefox uses certificates on secure websites to ensure that your information is being sent to the intended recipient and can"t be read by eavesdroppers. An incorrect system date can cause Firefox to detect that the website"s security certificate is expired or invalid. Make sure your computer is set to the correct date, time and time zone. For more information, see

Due to the increasing blocking of web resources, an increasing number of users have to deal with access errors. However, they may not always be associated with blocking sites by providers, the problem may be hiding on the computer itself. This is the error, and it does not matter which browser is used.

The error may occur due to the lack of a certificate confirming the safe operation of the browser with this site SSL , also the reason for its appearance may be related to changes in the settings of the software responsible for the security of the system. Today we will look at one of the most common variants of the error above, in which the user receives a notification "Website URL sent an invalid response. ERR_SSL_PROTOCOL_ERROR" .

With a greater degree of confidence, we can say that everything is in order with the site itself, however, check its availability using some service like ping-admin.com doesn't hurt either. If the resource is available, you should look for the causes of the error on the computer. There may be several reasons. If the site uses the connection HTTPS first you can check if the protocols are enabled SSL2 And SSL3 in the browser properties. Open the classic control panel, launch the applet.

Switch to tab "Additionally" and make sure that in the checkboxes SSL 2.0 And SSL 3.0 checkboxes are set.

Check if it matches time on a PC with your timezone. If not, set the correct time and enable synchronization.

Alternatively, you can try disabling protocol filtering HTTPS , although this is undesirable, as it reduces the level of security. In , for example, this can be done as follows. Navigate to internal address chrome://net-internals/#hsts , select from the menu on the left HSTS, in field "Delete Domain" paste the address of the problem site without the prefix HTTPS and press "Delete".

After that, you will be able to enter the site using the usual protocol. HTTP .

Note: before making changes to the protocol processing settings, you must completely clear the browser cache and delete saved files cookies and then try to visit the site. If the login succeeds without errors, with filtering disabled HTTPS may not be in a hurry.

It is very likely that access to the site is blocked by the anti-virus software installed on the computer. Sometimes the cause of the error becomes apparent after enabling private mode in the browser (incognita). Here, for example, is what when you go to a blocked site in incognito mode. In this case, the error "This site cannot provide a secure connection" calls the antivirus .

Therefore, you must either disable real-time protection in this program, or add the blocked site to the list of exceptions.

The settings of other anti-virus software are checked in the same way. In particular, users had to deal with the described error Dr. Web (firewall settings) And ESET NOD32 (SSL/TLS protocol filtering setting) . At the same time, it is necessary to check the operation of the extensions installed in the browser, since some of them, in particular, SaveFrom.net may interfere with the normal operation of network resources. And the last. If you get an access error when opening a site, use the most common anonymizer, or even better VPN -service, in most cases, these tools allow you to bypass such restrictions.

Tags: ,

Sometimes, and quite often, users, when trying to log in to a certain Internet resource, receive a message stating that an error occurred while establishing a secure connection. How to fix such a failure, now it will be considered. Depending on the situation, several different methods can be used.

What does it mean: "An error occurred while establishing a secure connection"?

First of all, you should clearly understand the problem of such a failure. The essence of the error is that the system, when accessing a certain site, needs to check the SSL certificate used for the HTTPS connection in order to authenticate the publisher.

However, several situations can be clearly identified when such a check gives a negative result, as a result of which a message is displayed stating that an error occurred when establishing a secure connection:

• mismatch of the date and time on the computer with the parameters of the Internet;
• outdated or expired certificate;
• certificate with incorrect serial number;
• OCSP server errors;
• incorrect browser settings (most often Mozilla Firefox);
• antivirus blocking.

Let's look at a few typical situations.

Error when establishing a secure connection: how to remove it in the simplest way?

Let's start with the most primitive way to troubleshoot. As mentioned above, the time set on the computer may not match the Internet settings. Therefore, these settings need to be changed.

Some users try to set the date and time directly in Windows, this does not give the desired result, and the error when establishing a secure connection appears again. Why? Yes, only because the setting must be done in the primary BIOS input / output system. That's when you can still count on something.

Disabling SSL and installing a certificate in antivirus

Antiviruses, compared to a firewall or Windows Defender, are much more likely to block such connections, considering the connection to be untrustworthy.

The solution to the problem can be either temporarily disabling protection, which is not very convenient, or setting the appropriate parameters. As a rule, such a section is located in the network settings. Here you need to disable SSL verification, and then use the "Certificate Installation Wizard", which will evaluate the validity of the connection, after which you just need to install the certificate. After confirming a successful installation, the problem should be gone.

Fixing a bug in browsers using Mozilla Firefox as an example

With browsers, things are a bit more complicated. As a rule, the message that an error occurred when establishing a secure connection is most often issued by the “fire fox”.

You can correct the situation as follows. First, with the browser turned off, you should go to the “Explorer” in your profile set for the browser (the profile folder is located on the system disk in the directory with the username of the Users directory, where you need to go to the AppData directory, then Roaming, then Mozilla, then Firefox , after that - Profiles, finally - ) and delete the cert8.db file in the final directory (folders are hidden, so you need to enable the display of such objects initially). Next, just launch the browser, the connection warning page appears, then click on the line that indicates that the user understands all the risks.

Note: additionally, in the security settings of tls_tickets, by double-clicking, you can change the value of the parameter to false. Just in case, you can check if the blocking AdBlock extension is enabled.

Problems with torrent trackers

Torrent trackers, as you know, the governments of many countries do not particularly indulge, believing that such sites host exclusively pirated content. To some extent it is, but not always. One such resource is the NNM.Club tracker. An error when establishing a secure connection on it appears quite often.

The tracker itself is now served exclusively at two addresses - 81.17.30.22 and 193.201.227.16. If something else is returned when pinging the address, then a spontaneous redirect is occurring. In this case, you just need to clear the DNS cache, see if there are any entries for these addresses in the HOSTS file at the very bottom of the text, and finally, you can simply set exclusion rules for these IPs in the antivirus or firewall.

In extreme cases, if it is problematic for an ordinary user to do this or the solution does not help, instead of a torrent file, you need to download the so-called magnet link and run it in the appropriate torrent program. In principle, the same applies to other trackers.

It is considered the most stable browser, while using it, some users may encounter various errors. This article will discuss the error "Error establishing a secure connection", namely, how to fix it.

The message "Error establishing a secure connection" can appear in two cases: when you go to a secure site and, accordingly, when you go to an insecure site. Both types of problems will be discussed below.

In most cases, the user encounters an error when establishing a secure connection when going to a secure site.

The user can say "https" in the address bar before the name of the site itself that the site is protected.

If you encounter the message "An error occurred while establishing a secure connection", then under it you can see an explanation of the cause of the problem.

Reason 1: The certificate will not be valid until date [date]

When you go to a secure website, Mozilla Firefox makes sure that the site has certificates to ensure that your data is transferred only to where it was intended.

As a rule, this type of error indicates that the wrong date and time are set on your computer.

In this case, you will need to change the date and time. To do this, click on the date icon in the lower right corner and select the item in the window that appears. "Date and time options" .

Reason 2: Certificate expired [date]

This error can also indicate an incorrectly set time, or it can be a sure sign that the site still did not renew its certificates on time.

If the date and time are set on your computer, then the site is probably the problem, and until it renews the certificates, access to the site can only be obtained by adding to the exceptions, which is described towards the end of the article.

Reason 3: The certificate is not trusted because its issuer's certificate is unknown

A similar error can occur in two cases: the site is really not worth trusting, or the problem lies in the file cert8.db, located in the Firefox profile folder that was corrupted.

If you are sure that the site is secure, then the problem is probably still a corrupted file. And in order to solve the problem, Mozilla Firefox will need to create a new such file, which means that you need to delete the old version.

To get to the profile folder, click on the Firefox menu button and in the window that appears, click on the icon with a question mark.

An additional menu will be displayed in the same area of ​​the window, in which you will need to click on the item "Problem Solving Information" .

In the window that opens, click the button "Show Folder" .

After the profile folder appears on the screen, you need to close Mozilla Firefox. To do this, click on the browser menu button and in the window that appears, click on the button "Exit" .

Now back to the profile folder. Find the cert8.db file in it, right-click on it and select "Delete" .

Once the file is deleted, you can close the profile folder and start Firefox again.

Reason 4: The certificate is not trusted because missing certificate chain

A similar error occurs, as a rule, due to antiviruses in which the SSL scanning function is activated. Go to your antivirus settings and disable the network (SSL) scanning feature.

How to resolve the error when going to an insecure site?

If the message "An error occurred when switching to a secure connection" appears if you go to an insecure site, this may indicate a conflict between settings, add-ons and themes.

First of all, open the browser menu and navigate to the section "Additions" . In the left area of ​​the window, by opening the tab "Extensions" , disable the maximum number of extensions installed for your browser.

Then go to the tab "Appearance" and remove all third-party themes, leaving and applying the standard one for Firefox.

After completing these steps, check for an error. If it remains, try disabling hardware acceleration.

To do this, click on the browser menu button and go to the section "Settings" .

On the left side of the window, go to the tab "Additional" , and at the top, open the subtab "Are common" . In this window, you will need to uncheck the box. "Use hardware acceleration whenever possible" .

Error workaround

If you're still unable to resolve the "Secure connection failed" message, but you're sure the site is secure, you can fix the problem by bypassing Firefox's persistent warning.

To do this, in the window with the error, click the button "Or you can add an exception" , then click on the button that appears "Add exception" .

A window will appear on the screen, in which click on the button "Get a Certificate" and then click on the button "Confirm Security Exception" .

Video lesson:

We hope this article has helped you troubleshoot Mozilla Firefox issues.