Event 1031 - Centralized URL Parsing

Logged Message

Centralized URL Parsing (CURL) assists in the prevention of malformed URLs fooling Windows Internet Explorer 8 and Windows Internet Explorer 7 by parsing the URL and verifying that it conforms to the Request for Comments (RFC) guidelines. When URL construction fails, it is typically because the URL does not conform to RFC guidelines. Internet Explorer 8 and Internet Explorer 7 log an error when URL construction fails, and a warning when a parsed URL results in a valid URL that is different from the URL parsed by Microsoft Internet Explorer 6. In this specific situation, Internet Explorer 8 and Internet Explorer 7 do not block the webpage; however, the page may behave contrary to expectations.

What Is It?

When a URL is entered into the address bar it is parsed to see if it adheres to RFC guidelines.

When Is This Event Logged?

This event is logged when URL construction fails.


Perform the following steps to see this event logged in the compatibility tool:

  1. Create a webpage with the following content. For this example call it 1031.html. The file can be placed anywhere. For this example, the file is located on the desktop.
    <html xmlns="http://www.w3.org/1999/xhtml" >
        <title> Centralized URL Parsing</title>
       <p>Link to URL with USERINFO: <a href="http://foo:bar@foobar1/">http://foo:bar@foobar1/</a></p>
  2. Open a browser and navigate to the webpage. For example: C:\Users\JohnS\Desktop\1031.html
  3. Click the hyperlink.

This causes the event to log to the compatibility tool. Windows Internet Explorer will also not allow the link to be clicked since the URL does not adhere to RFC guidelines and security best practices.


There is no workaround. Domain names are required to conform to the RFC guidelines.

Related topics

Internet Explorer Application Compatibility
Events 1030 through 1037