Agree that the situation when, when entering a page on a social network or portal of your favorite audio or video hosting, for some unknown reason, the browser suddenly displays a message stating that the site uses an unsupported protocol, although everything was fine up to a certain point, can put anyone in a stupor. Many users do not fully understand why such an unexpected failure occurred, and, alas, they do not know how to fix the situation. By and large, there is nothing wrong with the above message or a notification that this site cannot provide a secure connection. Below are some basic techniques that allow you to restore access to any resource. But first, you should clearly understand what such notifications mean and what is the reason for their appearance.
Message aboutthat the site is using an unsupported protocol: what does this mean and why?
Most experts explain the appearance of such errors with the subsequent issuance of messages by the fact that a secure connection cannot be provided on the part of the developer or resource owner, which applies to both secure (HTTPS) and regular (HTTP) protocols, problems namely SSL connections. Also, the occurrence of such a situation can also be noticed in cases where your browser and the requested page use, say, incompatible fonts that simply cannot be loaded or displayed in the browser you are using. But the saddest thing about all this is that most often for some reason this problem appears when you try to enter popular social networks (OK, VK), YouTube video hosting, antivirus portals, etc.
As for the reasons for notifications that this site cannot provide a secure connection, among them the most common are the following:
- problems on the side of the resource owner;
- presence of viruses on your computer;
- detection of viral activity on the site or blocking of the resource by antiviruses due to its definition as potentially dangerous;
- violations in the operation of network devices;
- the presence of computer debris (temporary files) in the system or in the browser;
- "gathering" of Internet connection settings;
- corruption of browser files or system components.
As you can see, to especially critical failures, allthe above cannot be attributed. However, immediately note that access problems related to violations in the operation of the resources themselves due to the fault of their developers or owners will not be considered.
The page uses an unsupported protocol: how do I access the site? The simplest solution
So, while trying to access a certain site, you received one of the above messages and the login was not possible. The simplest way out of this situation will be the most common page refresh by pressing the appropriate button in the browser or the F5 key (sometimes the combination Ctrl + F5 can be used). Naturally, you should not rely on such a solution, so let's proceed to the next steps.
Checking for viral activity
As already mentioned, the resource may "refuse" to accept your request, issuing a notification that the site uses an unsupported protocol, only because increased virus activity was detected on your terminal (from its point of view), which theoretically can lead to its infection, which will lead to a malfunction. Take the time and just in case, perform a full scan of your system for the possible presence of virus threats and dangerous applets using portable utilities. To detect and neutralize common viruses, use KVRT or Dr. Web CureIt, and for ad applets use AdwCleaner.
What to do with antivirus?
The opposite situation is not ruled out, when the antivirus installed on your computerwill block the requested resource due to its unreliability or the presence of potentially dangerous content on it. Visiting such sites while ignoring security notices is not recommended.

However, if you are sure that the resource is safe, just disable your antivirus for a while and try logging in again. If successful, add the site to your antivirus and firewall exceptions list.
The nuances of solving the problem when using a wireless connection
Quite often you can meet another situation, the occurrence of which may be associated with a banal "rally" of the router settings. In this case, the issuance of messages that the site uses an unsupported protocol is also not excluded. How to fix such a failure? Perform a full reset of the router settings, but not by pressing the Reset button on the rear panel, but by completely turning off the device for about 10-15 seconds and then turning it on.
Cleaning up junk in the system and browsers
Often, the presence of a huge amount of temporary files, including cached data (both in the browser and in the operating system itself) can often lead to notifications that the site uses an unsupported protocol in Chrome or in other browsers).

In this case, it is recommended to clear the history with the removal of all temporary components directly in the one used for working with the Internetbrowser.

Also, it doesn't hurt to find all TEMP system directories by typing %TEMP% in the Run console and then deleting absolutely everything they contain.
Reset internet settings
Incorrectly set Internet settings can also cause such errors. Perhaps, for some reason beyond your control, their parameters have been changed (for example, due to system failures). At the same time, similar to the previous situations, a notification is issued that the site uses an unsupported protocol.

In Windows XP, to fix the failure, use the Internet properties section in the Control Panel, and on systems of a higher rank, use the browser properties item, then on the content tab, click the SSL clear button.

After that, it is strongly recommended to enable advanced options by pressing the button on the advanced options tab, and if this does not work, perform a hard reset (Windows 10 may not have a second button).
Additional DNS settings
If the previous solutions did not work, and the message that the site uses an unsupported protocol appears again and again, check the DNS server settings in the properties of the IPv4 protocol. It is desirable to set them for automatic receipt.

If the effect is zero again, clean upDNS cache by typing ipconfig /flushdns.

If this does not help, in the IPv4 protocol parameters, instead of the specified DNS values or automatic address acquisition, enter combinations from Google, consisting of a set of eights and fours. Access to these DNS servers is absolutely free. You can also use any other combinations that are freely available on the Internet (for example, from Yandex).
Reset browser settings
If the browser, even after such drastic measures, does not respond to your requests and again displays a message stating that the site uses an unsupported protocol, in Yandex browser, in Chrome, in Opera or in any other browser used, perform a full resetting the settings to the initial state. To do this, any browser has a special section where you need to click just one button, then restart the browser and try to enter the site again.
Checking system components
Finally, if nothing helps at all, but you are sure that there are definitely no problems on the side of the requested resource (for example, you can access the site from a mobile phone), there is only the last resort, which involves performing a full check of the system components with their subsequent restoration, if possible.

Run the command console asadministrator, run the sfc /scannow command and wait for the results of the scan and repair.
Note: if in normal mode it is reported that recovery is impossible, follow the same steps by booting into safe mode, or when starting from removable media with a Windows installation distribution or recovery environment (LiveCD), selecting start via the recovery partition command line.