1. Check the Date of Your System
When the date of your computer is not in sync with the date of the server that you’re trying to access you’ll face the problem of ERR_SSL_PROTOCOL_ERROR on your Chrome browser. The fix is to adjust the date of your system to the current date.
2. Clear Browsing Date
If the date on your computer is right, follow the steps given below to delete browsing data from your Chrome browser:
§ Launch Chrome;
§ Press Ctrl + Shift + Delete;
§ Ensure that the time range is set to “All Time”;
§ Check the checkbox for “Cookies and other site data”;
§ Check the checkbox for “Cached images and files”;
§ Hit Clear Data
3. Clear Your SSL State
§ Click on the 3 dots showing next to the address bar in Chrome, right below the close button of the browser.
§ Click Settings and scroll all the way down to Advanced Click on the button to expand Advanced settings;
§ Now scroll down to “Open Proxy Settings” option under System section and click on it;
§ A window named “Internet Properties” will open. Go to Content tab in that window and click on Clear SSL State
4. Disable QUIC Protocol of Chrome
§ Paste chrome://flags/#enable-quic in the address bar of your Chrome browser and hit Enter;
§ Under Experimental QUIC Protocol option, you’ll see that it’s set to “Default”. Disable it.
5. Check Your Antivirus Settings
All modern antivirus programs scan the websites for malicious elements and other security threats, which also includes checking the SSL/TLS version of a site. If a website is using an outdated version of SSL, the antivirus blocks it and doesn’t allow us to visit it. In this case, the problem can be solved by disabling the antivirus temporarily. Just turn off your antivirus for a while and see if you can open the error generating website or not.
6. Check Your Firewall
If a website is present in the blocklist of your Internet Firewall, Chrome will obviously not be able to open it. Check your Firewall to ensure that the website you’re trying to visit is not present in its blocklist. If you find it there, remove it and try loading the website again.
7. Disable Extensions
Disable your Chrome extensions one by one and open the error generating website again and again as you do that. If you find any extension to be the culprit, remove it.
8. Adjust Your Internet Security and Privacy Level
§ Type “Internet Options” in the search bar of your computer and hit Enter;
§ The “Internet Properties” dialogue box will open. Inside it navigate to Security tab and look at the slider given there. If that slider is too high on the scale, bring it in the middle (to Medium level) and click OK.
Now try opening the website that you were trying to open.
Out of above-given methods at least one will certainly solve your problem of ERR_SSL_PROTOCOL_ERROR on Google Chrome. Try out each of them until you find your solution.