.PS1XML File Extension
File TypeWindows PowerShell Display Configuration File
What is a PS1XML file?
Configuration file used by Windows PowerShell, a shell program included with Windows 7; contains XML definitions for how output is displayed within the console; used for formatting directory listings, help pages, registry information, and other output.
Windows PowerShell includes several PS1XML files as part of the installation. These files are somewhat complicated and should not be edited without a good understanding of their content.