If you’re using Chrome to connect to an HTTPS-enabled CA server and receiving the error “Err_Http2_Inadequate_Transport_Security.” Then there’s likely an issue with the server’s security configuration. Windows Server deployments frequently experience this problem.

In the age of the internet, encountering browser errors is not uncommon. However, while some errors are relatively straightforward, others can be a bit perplexing.

One such error message that has stumped many users is the Err_Http2_Inadequate_Transport_Security on Google Chrome. In this guide, we will dive deep into this error, understand its causes, and look at potential solutions.



What Does Err_Http2_Inadequate_Transport_Security Mean?

This error message appears when Google Chrome detects an issue with the website’s server configuration concerning the HTTP/2 protocol.

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The error indicates that the website is using a combination of the HTTP/2 protocol and a cipher suite that Chrome deems insecure. In simple terms, the error arises from a mismatch in security protocols between the server and the browser.

What Causes Err_Http2_Inadequate_Transport_Security Error on Google Chrome?

The primary cause of this error is the website’s server configuration. The HTTP/2 protocol, which provides a more efficient and faster connection than its predecessor, HTTP/1, has specific security requirements. Here are the main causes:

  1. Cipher Suite Mismatch: HTTP/2 mandates the use of specific cipher suites, considered modern and secure. If the server is configured to use cipher suites not sanctioned for HTTP/2, this error will arise.
  2. Outdated Server Configuration: Servers not updated or configured to the latest security standards can lead to this error. An outdated TLS version or unsupported cipher suites are typical culprits.
  3. Browser-Side Issues: Sometimes, the error can also stem from the user’s browser, especially if the browser is outdated or has corrupted files.

How to Fix Err_Http2_Inadequate_Transport_Security?:

Google Chrome is a robust browser, but it isn’t without its share of flaws. The Err_Http2_Inadequate_Transport_Security error is well-known for indicating incompatibility between Chrome and other browsers’ security protocols.

Fortunately, fixing this mistake is easier than it looks. As long as you follow the steps outlined in this manual, you should have no trouble getting it fixed.

Solution 1: Update Google Chrome to the Latest Version

Before anything else, check to see that you’re running the most recent stable version of Google Chrome. If you’re having trouble connecting to an HTTPS-enabled CA server from a Windows Server installation, this is crucial information.

Evidently, the Err_Http2_Inadequate_Transport_Security problem you’re experiencing is due to the fact that your version of Google Chrome lacks certain necessary security components.

Multiple people experiencing the same issue have reported that upgrading to the most recent version of Google Chrome has resolved the issue permanently.

Solution 3: Update Google Chrome

If you’re using an older version of Chrome that’s missing some security mechanism, you’ll get the Err_Http2_Inadequate_Transport_Security error message. This can be resolved by upgrading to the most recent version of your browser.

There are a few prerequisites for accomplishing this:

Step 1: First, launch Chrome and navigate to the menu bar.

Step 2: The second step is to go to Chrome’s settings by clicking the About button.

Solution 3: Update Google Chrome

A transport security error of type Err_Http2_Inadequate_Transport_Security. Those who have migrated from IIS to Windows Server and are concerned about security may wish to turn off HTTP/2 on Windows Server.

Step 1: In a Notepad window with administrative privileges, copy and paste the code below.

Windows Registry Editor Version 5.00




Step 2: To save the registry file, go to File > Save As and change the Save as type to All Files.

Step 3: Right-click on the registry file and pick Run as administrator in the drop-down menu.

Step 4: Restart Windows Server installation to save the changes.

Solution 4: Clear Browser Cache and Cookies

Websites run faster in part because of cache files, which keep track of your browser history and other data. However, if you don’t clear your cache and restart your computer occasionally, the files in it could become corrupted.

Browser crashes and problems are often the result of corrupted files interfering with the browser’s own files. Similarly, cookies are pieces of data that can be used to monitor your browser and glean information about you.

Since many websites urge you to accept cookies, the collected pile of these cookies can also contribute to typical Chrome issues.

How Do I Disable HTTP/2 in Chrome?

While disabling HTTP/2 is not recommended because of the performance benefits it provides, if you need to do so for troubleshooting purposes, follow these steps:

  1. Right-click on your Google Chrome shortcut.
  2. Choose ‘Properties.’
  3. In the ‘Target’ field, after the path to Chrome, add a space and then add --disable-http2.
  4. Click ‘Apply’ and then ‘OK’ to save changes.

Remember to remove this flag once you’re done troubleshooting, as you would be foregoing the benefits of HTTP/2.

What Are the TLS Requirements for HTTP/2?

To maintain a secure environment, HTTP/2 has established specific Transport Layer Security (TLS) requirements. Here’s what’s mandatory:

  1. TLS Version: HTTP/2 requires the use of TLS 1.2 or higher.
  2. Cipher Suites: HTTP/2 has banned several cipher suites that were permissible in HTTP/1 for security reasons. Cipher suites using block ciphers, RSA key exchange, and those without forward secrecy are disallowed.
  3. Compression: The “compression” feature of TLS is disallowed in HTTP/2 due to vulnerabilities.
  4. Extension ALPN: The Application-Layer Protocol Negotiation (ALPN) extension is necessary, allowing the client and server to choose which protocol to use (i.e., HTTP/1.1, HTTP/2).

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Chrome is a good browser, but it has a bad reputation for being unstable and prone to bugs. The “err http2 inadequate transport security chrome” is one example of such a message. You may also encounter a notice along the lines of “This site is unable to access this page.”

This error suggests that Chrome’s security mechanisms are not fully compatible. One of the major causes of this error is that there’s no proper data flow with the revised network protocol, i.e., HTTP/2 on Windows server and Chrome.

Cookies, cache files that have become corrupted, and flaws introduced by an out-of-date version of Chrome are also possible causes.

Encountering the Err_Http2_Inadequate_Transport_Security error can be frustrating, but understanding its roots can ease the troubleshooting process.

While the error primarily points towards server-side issues, it’s always advisable for both website administrators and users to keep their systems, servers, and browsers updated to the latest standards. Regular updates and adherence to security protocols will not only ensure a smoother browsing experience but also a safer one.