Microsoft officially ended support for MSXML 4.0 in April 2014 .
Note. Support for XML Core Services 4.0 has ended. Support was only available for Service Pack 3. Microsoft Learn Microsoft Msxml 4.20.9818.0
Because it no longer receives updates, it is frequently flagged by security scanners (like Nessus or Qualys) as a vulnerability. Microsoft officially ended support for MSXML 4