Workaround for when a site won't open and displays "Unsupported protocol is being used"

Hello.
the Scytale Cryptographic
Systems Solutions Department, handling internal communications.

It's May.
The Golden Week holidays are over, how is everyone doing? Personally, to prevent the May blues, I wish they'd create a rainy day (a national holiday) in June, which has no public holidays. (I'm asking someone in a position of power to do it.)

Now, this time I'd like to write about a tip, or rather a workaround, for the issue where, when you access a website from your browser, you get the message, "This site cannot be accessed securely. An unsupported protocol is being used," and the site won't open.

Savior IE

In short, you can open it by making a few minor changes to the Internet Explorer (IE) settings.

The reasons and methods will be explained later, but as a precaution,trusted websitesplease only use the methods described in this article on

Why can't you open it in the first place?

ERR_SSL_VERSION_OR_CIPHER_MISMATCH
, it's possible that the SSL/TLS version you're using is not permitted.

Simply put, SSL/TLS is a protocol that encrypts data when you access a website, ensuring secure data exchange.
Since this protocol uses HTTPS and encrypted communication, we'll be using SSL/TLS.

While this article won't go into too much detail, this protocol, originally implemented under the name SSL,has known vulnerabilities.
For example, SSLv3, the latest version of SSL,POODLE , which allows a third party to intervene in the communication (man-in-the-middle attack) and decrypt and intercept the exchanged data.

This history has repeated itself, and now the TLS protocol, a more advanced version of SSL, is primarily used.
TLS currently exists in versions 1.0 through 1.3, but since 1.3 is relatively new, 1.2 is currently the mainstream.
Other protocols like QUIC and HTTP/3 have emerged, but we'll discuss those another time...
(As an aside, in spoken language, "SSL" is still more common than TLS, even though it's not used anymore. It's interesting how legacy things change.)

SSL/TLS support for major browsers

In relation to the aforementioned vulnerability, there was a period when each browser actively took measures to address it

For example, my go-to browser, Firefox,this featurehas implemented

Starting with Firefox version 78, the minimum TLS version allowed by default is TLS 1.2. Websites that do not support TLS version 1.2 will display an error message with the error code: SSL_ERROR_UNSUPPORTED_VERSION, indicating that the secure connection could not be established. This may be because the website does not support the TLS 1.2 protocol, which is the minimum version supported by Firefox. Enabling TLS 1.0 and TLS 1.1 may allow the connection to be established.
- From Firefox Help

Google Chrome, the undisputed leader in browser market share,measures to block access using TLS 1.0 and 1.1 as of March 2020(of course, similar measures were taken for older SSL versions much earlier). It seems to be the way things are going.

Since Microsoft Edge is also Chromium-based,disabled TLS 1.0 and 1.1 by default in July 2020it seems

If Edge doesn't work, just use IE

Sorry for the wait. Now the real action begins
In fact, onceHe should have been buriedUse Internet ExplorerIsn't it more tenacious than the Tyrant from Biohazard?
(Chrome and Firefox also have options, but I use them for work and find them a bit of a hassle, so I'll use IE for simplicity.)

Since my PC runs Windows 11, I will explain the procedure using Windows 11.
this methodon trusted websitesplease

1. Open Microsoft Edge and open the hamburger menu in the top right corner

2. Click [More Tools] -> [Internet Options]

3. From the [Details] tab, check whether the TLS version in the red box is set to be used. If it is not, check it to enable it and then apply it. (We recommend disabling SSL 3.0.)

4. Select [Settings] from the hamburger menu again to display the menu list, then click [Default browser]

5. Change the [Default] setting in [Allow sites to be reloaded in Internet Explorer mode (IE mode)] to [Allow] and click [Restart] to reload the browser

6. From the left-hand menu, go to "Appearance" → "Customize Toolbars" → enable the "Internet Explorer Mode (IE Mode) button"
(you'll find various methods if you search online, but personally, I think this is the easiest).

7. After activation, when you navigate to a page that you couldn't open before, you should see a familiar icon added to the top right menu. Click it

, and you will see a message like the one below, allowing you to load the page in IE mode.

If you want to open pages in IE mode from now on, enable the area highlighted in red. Once you're finished, click [Done].

8. As shown in the example below, a menu will appear titled [▼More information] → [Go to web page (not recommended)]. Clicking this will allow you to view the page

Final note

I think this will allow you to open most websites

due to its low securitynot recommended. It is
recommended unless your company's server is running CentOS 6, you are using a self-signed certificate in your local environment, or your firewall is too old to support anything other than SSL.

See you later!

complete

Added on 2024/2/27

Microsoft Edge version 122.0.2365.52 I'm adding this note because the UI has been slightly changed in

First, the page display for when a file fails to open has been changed in the version mentioned above. It's
a bit more stylish. The wording is the same.

But don't worry. IE mode is still available, sothe settingsopen

[Appearance] → [Allow sites to reload in Internet Explorer modeGo to

[Default browser[Allow sites to reload in Internet Explorer mode] to [Allowchange

to apply the settingsRestart, and Microsoft Edge will close once and restart automatically.

A new feature has been added that allows you to add pages individually, so you may want to add URLs if needed.

After restarting, if you try to open a page that wouldn't open before,More informationyou should be able to open the page from