ERR_SPDY_PROTOCOL_ERROR' is an error in the Chrome browser which can appear for some different reasons, both with and without the VPN. Please try the solutions below.
1. Restarting your browser
When you face this error, you can close your chrome browser and start it again. It should fix ERR_SPDY_PROTOCOL_ERROR. While this is a simple fix, it is the quickest way to solve this error.
2. Make sure your Chrome browser is up to date
You can easily update your Chrome browser via the settings menu on the upper right of your browser window, and selecting "About Chrome".
3. Use Chrome’s Incognito Mode
If you face ERR_SPDY_PROTOCOL_ERROR for any specific website, you can try to access that website in incognito mode (CTRL + SHIFT + N).
4. Check Antivirus / Firewall Setting
If you are using Avast antivirus or any other product of Avast possibility is that it is due to the Avast Security Software. You have to follow these steps to add the website in web shield exclusion of Avast Software.
Click on the setting Icon on Avast Antivirus then active protection and Customize for web shield option. Add your blocking website to the exclusion list and try to open the website in chrome after clearing your cache.
Or if you are getting errors for lots of sites with https enabled. Please try disable the HTTPS Scanning option in Avast Web Shield main Setting as in below screenshot.
Settings -> Active Protection -> Customize for Web Shield
5. Flushing DNS and Renewing IP
Flushing DNS and Renewing IP can solve ERR_SPDY_PROTOCOL_ERROR sometimes.
To flush DNS:
- Open Command Prompt.
- Type ipconfig /flushdns and press Enter.
To Renew IP:
- Open Command Prompt.
- Type ipconfig /release and press Enter.
- Again type ipconfig /renew and press Enter.
Note: You may need to also configure your internet connection.
5. Flushing SPDY Sockets
To flush SPDY sockets:
- Go to chrome://net-internals/#events&q=type:SPDY_SESSION%20is:active from your chrome browser.
- Then click on the arrow of the top right corner.
- From the drop-down menu select Flush Sockets.
