If you find yourself in the regular command line (cmd.exe) on Windows and you’d like to run a PowerShell script, you can do it like this:
> assoc .ps1=Microsoft.PowerShellScript.1
> ftype Microsoft.PowerShellScript.1="%SystemRoot%\system32\WindowsPowerShell\v1.0\powershell.exe" "%1"
This tells Windows that files with the .ps1 file extension should be considered executable, that their file type should be Microsoft.PowerShellScript.1 and that this file type should be sent as a parameter to the PowerShell executable.
You might want to check if there is something registered for this file type already before you do this. To do that simply run
assoc .ps1 and
ftype Microsoft.PowerShellScript.1. For me the file type was already associated with ps1 files, but the handler was set to notepad for some reason.
Either way, after opening up a new command prompt (to make sure the new PATHEXT environment variable is loaded), you should be able to run a PowerShell scripts directly just like .bat and .exe files: