Running a psm1 PowerShell script in Command Prompt (cmd.exe)?

Question

I know nothing of PowerShell, but I wanted to install this: https://www.powershellgallery.com/packages/lolcat/

So, I start PowerShell as administrator, and:

PS C:\WINDOWS\system32> Install-Module -Name lolcat                                                                                                                                                                                             NuGet provider is required to continue
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PS C:\WINDOWS\system32> lolcat

Usage: lolcat [OPTION]... [FILE1[, FILE2[, ...]]]
...

Nice, it works. So first I find where is the newly installed script:

PS C:\WINDOWS\system32> (Get-Module lolcat).Path
C:\Program Files\WindowsPowerShell\Modules\lolcat\1.0.7\lolcat.psm1

Ok, so now I want to try calling this from cmd.exe:

C:\Users>PowerShell.exe -File "C:\Program Files\WindowsPowerShell\Modules\lolcat\1.0.7\lolcat.psm1"
Processing -File 'C:\Program Files\WindowsPowerShell\Modules\lolcat\1.0.7\lolcat.psm1' failed because the file does not have a '.ps1' extension. Specify a valid Windows PowerShell script file name, and then try again.
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Nope, does not work.

Is it possible to call this PowerShell script from cmd.exe - and if so, how?

Answer 1

The error is due to the fact that the -File parameter from the powershell.exe excepts a .ps1 file.

If you want to run C:\Program Files\WindowsPowerShell\Modules\lolcat\1.0.7\lolcat.psm1 from cmd, make a .ps1 script where you can write something like

Import-Module lolcat

# now you have all the functions from the lolcat module loaded into this PowerShell session

# do stuff

And then call this script from cmd.

The difference between .ps1 and .psm1 is explained here .

Answer 2

Eh, turned out to be less complicated then I thought - since it is a "module", just use the module name:

C:\Users>PowerShell.exe lolcat

Usage: lolcat [OPTION]... [FILE1[, FILE2[, ...]]]

...