Since Windows 10 build 1803 from April 2018, the XPS Viewer is no longer included by default in that build of the operating system and has to be installed manually.
Usually this is done by browsing to the applications and feature pane but sometimes cannot be found and installed this way. The quickest and most efficient way is using the command line.
1. Open the Command Prompt (or PowerShell) with elevated privileges :
Right click on the Windows button, then “Command Prompt (Admin)” or “Windows PowerShell (Admin)”
2. Enter the following command to request the installation of the XPS Viewer component :
dism /Online /Add-Capability /CapabilityName:XPS.Viewer~~~~0.0.1.0