Fixing HTTP Error 404.11: Not Found Due to Double Escape Sequences | Sports News Website

• The request contained a double escape sequence, and request filtering configured on the web server rejects double escape sequences.

• Confirm the configuration/system.webServer/security/requestFiltering@allowDoubleEscaping setting in the applicationhost.config or web.confg file.

This is a safety feature. Please do not change this feature unless you are fully aware of the scope of the change. Before changing this value, a network trace should be performed to confirm that the request is not malicious. If your server allows double escape sequences, modify the configuration/system.webServer/security/requestFiltering@allowDoubleEscaping setting. This may be caused by a malformed URL sent to the server by a malicious user.

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