Is there a way to supress any interactive prompts in a PowerShell script?

Question

When writing PowerShell scripts, I noticed when certain cmdlets encounter problems they bring up an interactive prompt, Remove-Item on a non-empty directory being an example. This is deadly when attempting to automate tasks, I'd much rather the action just fail and either throw an exception or return a bad return code so that the entire script isn't locked up waiting for a response.

Is there any way to force PowerShell to automatically fail as opposed to seeking user input on actions?

Answer 1

The solution proposed by Eris effectively starts another PowerShell instance. An alternative way to do this, with simpler syntax, is to shell out to another instance of powershell.exe.

powershell.exe -NonInteractive -Command "Remove-Item 'D:\Temp\t'"

Answer 2

See Get-Help about_Preference_Variables:

$ConfirmPreference
------------------
    Determines whether Windows PowerShell automatically prompts you for
    confirmation before running a cmdlet or function.

...

None:    Windows PowerShell does not prompt automatically.
                         To request confirmation of a particular command, use
                         the Confirm parameter of the cmdlet or function.

So:

> $ConfirmPreference = 'None'

Answer 3

Ok, This is really ugly, but holy mustard stains it "works".

Issues:

• I have not figured out how to continue after the first error
• In this case, it removes plain files, then stops at the first folder
• I have not figured out how to make this cmdlet work if I add the UseTransaction parameter

• This will only work for the Simple case (commands that don't do a lot of stuff with the current environment). I have not tested anything complex

  $MyPS = [Powershell]::Create()
$MyPS.Commands.AddCommand("Remove-Item")
$MyPS.Commands.AddParameter("Path", "D:\Temp\t")
$MyPS.Invoke()

Output:

Commands                                                                                                                 
--------                                                                                                                 
{Remove-Item}                                                                                                            
{Remove-Item}                                                                                                            
Exception calling "Invoke" with "0" argument(s): "A command that prompts the user failed because the host program or the 
command type does not support user interaction. The host was attempting to request confirmation with the following 
message: The item at D:\Temp\t has children and the Recurse parameter was not specified. If you continue, all children 
will be removed with the item. Are you sure you want to continue?"
At line:19 char:1
+ $MyPS.Invoke()
+ ~~~~~~~~~~~~~~
    + CategoryInfo          : NotSpecified: (:) [], MethodInvocationException
    + FullyQualifiedErrorId : CmdletInvocationException

Answer 4

I was also having the same issue. The solutions tried by me included:

• ECHO 'Y' |
• Command-Name -Force
• $ConfirmPreference = 'None'

However, none of them seemed to do the trick.

What finally solved the problem was:

Powershell-Cmdlet -Confirm:$false

It suppresses all confirmation prompts for the duration of the command and the command would be processed without any confirmation.

Answer 5

All of the above solutions failed for me when I was create a directory, which meant that I was prompted to OK every single directory that my script created - which was a lot. What worked for me was to apped | Out-null in order to pipe the results to Out-Null

New-Item -ItemType Directory -Path $directory -Force:$doForce | Out-Null

Note that $Directory is a string with the full path to the directory you want to create. Hope this saves somebody some time :P

Answer 6

I suggest two techniques

a) Append -force

b) Append -errorAction silently continue

This is how I research which cmdlets support a particular parameter

Get-Command | where { $_.parameters.keys -contains "erroraction"}

Answer 7

I was trying to do the following:

net use * /delete

And it prompted me every time to answer yes or no. Solution that worked for me and may work in other cases:

net use * /delete /y