I am receiving an error code when trying to access certain webpages. "521 An error occurred while attempting to load this content."

Question

After setting up my new computer with Windows 11 I am unable to sign in to certain established webpages. I am receiving the below message.... According to AI this is related to Cloudflare. Is my server Microsoft Copilot? And, how can I fix this?

521

An error occurred while attempting to load this content.

Answer 1

Error 521 is a Cloudflare error. It means Cloudflare cannot connect to the website’s own server, usually because that server is offline or refusing the connection. Microsoft Copilot is not your server, and reinstalling Windows should not be necessary. Cloudflare’s explanation is here: https://developers.cloudflare.com/support/troubleshooting/http-status-codes/cloudflare-5xx-errors/error-521/

Disclaimer: This link points to a non-Microsoft official website. The page content appears accurate and safe, but the website may contain third-party advertisements. Please distinguish between advertisements and official download links to avoid accidentally clicking on content that may promote PUPs/PUAs (potentially unwanted programs). Before downloading or installing any files, it is recommended to verify the source and file name.

First, open the affected website in an Edge InPrivate window by pressing Ctrl + Shift + N. If it works there, clear the cookies and cached files for that website: https://support.microsoft.com/en-us/edge/view-and-delete-browser-history-in-microsoft-edge

Also temporarily disable any VPN, proxy, browser extension or antivirus “web protection,” then test the website using another browser or a phone hotspot.

If the same 521 error appears on another device or network, the problem is with the website’s server. Contact the website owner and provide the page address, time of the error, screenshot and Cloudflare Ray ID shown on the error page.