See How to run PowerShell script without terminal window?

Use the Start-Transcript and Stop-Transcript to create transcript of the script running as a job. Hopefully you'll see the issue more clearly i.e. Module not importing or similar.

I've just tried line two '*\*' and it worked as expected for me (no escape needed). I used cmd to run the bat file containing the PowerShell code.

Do you need to read the actual command in the file, as in, it could be base64 encoded. I could provide an example if needed.

The reason replace works with "\\" is that it uses regular expression where as like uses wildcard expressions (different syntax and escape methods)

Try using Format-Volume with the -Full switch.

The issue here is when you run the .bat file it will run using cmd which has a different interpreter than PowerShell, for example the method you've used to pass the array will not work in cmd and is why the statup.bat fails. For a simpler life, pick one, either cmd and bat or PowerShell and ps1.

Don't Format-Table when creating your $users array. Remove this and try again.

I suspect 1.14.2281.0 is your Windows Terminal version. Could you run $PSVersionTable.PSVersion.ToString() so we can understand what version of PowerShell you're running and update the question with the output.

$args is an array of values for undeclared parameters that are passed to a function and you only passed declared parameters. I suggest you have a read of Get-Help about_functions and try the examples.

Try """reg import ""C:\Program Files\MyCompany\site1.reg"""