If you see an error message Windows cannot find Powershell.exe, first check whether Windows PowerShell is Enabled, and then follow these suggestions.

If Windows PowerShell has stopped working & is not opening or launching, due to Restrictions in effect, No app associated with it, etc. see this post.

Windows PowerShell has evolved into a command-line utility essential for system administrators and advanced users. The tool provides an intuitive interface to automate and manage various Windows ...

Having spent time with System Center Virtual Machine Manager 2012, Brien began looking at how much of what this product does could also be done through PowerShell.

System Center Operations Manager 2007 Unleashed also includes examples of using PowerShell for OpsMgr administrative tasks.