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Quick Guide To Fix Error Message: err_ssl_server_cert_bad_format

Google chrome is one of the popular and widely used web browsers throughout the globe. Many users rely on it, and it’s no exception that sometimes unwanted error messages do occur when someone tries to open the website. Some are common, and some are quite unheard such as err_ssl_server_cert_bad_format.

If you think what does this error message means or how to solve it, then you’re not alone. It’s not an error that is seen often, so it’s quite apparent that you might question how come this error message occurred.

Let’s get into details.

What Does This Error Message: err_ssl_server_cert_bad_format Means & What causes it?

It’s one of the SSL based errors that occurs whenever you try to visit a website that has a self-signed SSL/TLS certificate installed instead of an SSL/TLS certificate provided by trusted Certificate Authority such as Sectigo or Comodo.

SSL/TLS Certificates provided by known certificate authorities are called trusted, and it’s accepted globally by all the popular web browsers like Google Chrome and Mozilla Firefox.


What is Self-Signed SSL/TLS Certificate?

Put simply, Self-signed SSL/TLS Certificate is the ones that are signed by the same individual to whom the certificate has to be issued. For example, owner of the website, signing an SSL certificate on their own for their site. Moreover, the signing procedure and the private key are not signed by any trusted Certificate Authority such as Sectigo but the owner of the website itself.

How to Solve This Error Message: err_ssl_server_cert_bad_format?

There’s a solution, but it’s temporary.

To solve this issue, follow the below steps:

Windows (10)

Click Windows icon at the bottom left corner and type Internet Options and open it by double-clicking on it.
It’ll open Internet Properties. From that, select the tab Security and double click on Trusted Sites. It’ll open Trusted sites pop up. Now, insert the URL of the website, which is showing an error message: err_ssl_server_cert_bad_format in the “Add the website to the zone:
Once you add the website URL, click Add button and then Close. Finally, click the OK button and try opening the website again.

Google Chrome

You can also try this option through the web browser. For example, in Google Chrome,

Click on three dots at the top right corner and click Settings.

From the left panel, click Advanced and select System.
Once it opens, from the right side, click Open your computer’s proxy settings.
It’ll open Internet Properties. Now follow the above steps mentioned for Windows (10).
However, this is not a permanent solution. Moreover, if you’re a website owner and trying to solve this issue permanently, then you will not be able to do so unless you get the certificate installed from a trusted certificate authority. Because, self-signed SSL/TLS certificate is not accepted by any web browser, because it has many drawbacks that are not acceptable to overlook. Besides, if anyone who installs a self-signed SSL certificate, their website visitors will face an error message.

Though, if you’re in doubt whether to go with the paid one or not from SSL/TLS certificate providers like RapidSSL, Sectigo, or Comodo, then there’s one more option of getting a free trial before making any final decision. For example, RapidSSL CA offers an SSL Certificate as a 30-day trial free of cost.


First and foremost, a self-signed SSL certificate must be avoided. Unless you’re using for testing purposes internally, then it’s a different thing. Moreover, if you’re a website visitor who’s facing this error message: err_ssl_server_cert_bad_format, then we recommend going through the steps mentioned above. If you’re a website owner, then we would say it’s better to install an SSL/TLS Certificate provided from a respected Certificate Authority.

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