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This is the built-in help made by Microsoft for the document 'about_Scripts', in PowerShell version 5 - as retrieved from Windows version 'Microsoft Windows Server 2012 R2 Standard' PowerShell help files on 2016-06-24.

For PowerShell version 3 and up, where you have Update-Help, this command was run just before creating the web pages from the help files.

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Describes how to run and write scripts in Windows PowerShell.

A script is a plain text file that contains one or more Windows PowerShell
commands. Windows PowerShell scripts have a .ps1 file name extension.

Running a script is a lot like running cmdlet. You type the path and file
name of the script and use parameters to submit data and set options. You
can run scripts on your computer or in a remote session on a different

Writing a script saves a command for later use and makes it easy to share
with others. Most importantly, it lets you run the commands simply by typing
the script path and the file name. Scripts can be as simple as a single
command in a file or as extensive as a complex program.

Scripts have additional features, such as the #Requires special comment,
the use of parameters, support for data sections, and digital signing for
security. You can also write Help topics for scripts and for any functions
in the script.


Before you can run a script, you need to change the default Windows
PowerShell execution policy. The default execution policy, "Restricted",
prevents all scripts from running, including scripts that you write on the
local computer. For more information, see about_Execution_Policies.

The execution policy is saved in the registry, so you need to change it
only once on each computer.

To change the execution policy, use the following procedure.

1. Start Windows PowerShell with the "Run as administrator"

2. At the command prompt, type:

Set-ExecutionPolicy AllSigned
Set-ExecutionPolicy RemoteSigned

The change is effective immediately

To run a script, type the full name and the full path to the script

For example, to run the Get-ServiceLog.ps1 script in the C:\Scripts
directory, type:


To run a script in the current directory, type the path to the
current directory, or use a dot to represent the current directory,
followed by a path backslash (.\).

For example, to run the ServicesLog.ps1 script in the local
directory, type:


If the script has parameters, type the parameters and parameter
values after the script file name.

For example, the following command uses the ServiceName parameter of
the Get-ServiceLog script to request a log of WinRM service activity.

.\Get-ServiceLog.ps1 -ServiceName WinRM

As a security feature, Windows PowerShell does not run scripts when you
double-click the script icon in File Explorer or when you type the
script name without a full path, even when the script is in the current
directory. For more information about running commands and scripts in
Windows PowerShell, see about_Command_Precedence.

Beginning in Windows PowerShell 3.0, you can run scripts from File
Explorer (or Windows Explorer, in earlier versions of Windows).

To use the "Run with PowerShell" feature:

In File Explorer (or Windows Explorer), right-click the
script file name and then select "Run with PowerShell".

The "Run with PowerShell" feature is designed to run scripts
that do not have required parameters and do not return output
to the command prompt.

For more information, see about_Run_With_PowerShell


To run a script on one or more remote computers, use the FilePath
parameter of the Invoke-Command cmdlet.

Enter the path and file name of the script as the value of the FilePath
parameter. The script must reside on the local computer or in a directory
that the local computer can access.

The following command runs the Get-ServiceLog.ps1 script on the Server01
and Server02 remote computers.

Invoke-Command -ComputerName Server01, Server02 -FilePath C:\Scripts\Get-ServiceLog.ps1


The Get-Help cmdlet gets the help topics for scripts as well as for
cmdlets and other types of commands. To get the help topic for a script,
type "Get-Help" followed by the path and file name of the script. If the
script path is in your Path environment variable, you can omit the path.

For example, to get help for the ServicesLog.ps1 script, type:

get-help C:\admin\scripts\ServicesLog.ps1


A script can contain any valid Windows PowerShell commands, including single
commands, commands that use the pipeline, functions, and control structures
such as If statements and For loops.

To write a script, start a text editor (such as Notepad) or a script editor
(such as the Windows PowerShell Integrated Scripting Environment [ISE]). Type
the commands and save them in a file with a valid file name and the .ps1 file
name extension.

The following example is a simple script that gets the services that are
running on the current system and saves them to a log file. The log file name
is created from the current date.

$date = (get-date).dayofyear
get-service | out-file "$date.log"

To create this script, open a text editor or a script editor, type these
commands, and then save them in a file named ServiceLog.ps1.


To define parameters in a script, use a Param statement. The Param statement
must be the first statement in a script, except for comments and any
#Requires statements.

Script parameters work like function parameters. The parameter values are
available to all of the commands in the script. All of the features of
function parameters, including the Parameter attribute and its named
arguments, are also valid in scripts.

When running the script, script users type the parameters after the script

The following example shows a Test-Remote.ps1 script that has a ComputerName
parameter. Both of the script functions can access the ComputerName
parameter value.

param ($ComputerName = $(throw "ComputerName parameter is required."))

function CanPing {
$tmp = test-connection $computername -erroraction SilentlyContinue

if (!$?)
{write-host "Ping failed: $ComputerName."; return $false}
{write-host "Ping succeeded: $ComputerName"; return $true}

function CanRemote {
$s = new-pssession $computername -erroraction SilentlyContinue

if ($s -is [System.Management.Automation.Runspaces.PSSession])
{write-host "Remote test succeeded: $ComputerName."}
{write-host "Remote test failed: $ComputerName."}

if (CanPing $computername) {CanRemote $computername}

To run this script, type the parameter name after the script name.
For example:

C:\PS> .\test-remote.ps1 -computername Server01

Ping succeeded: Server01
Remote test failed: Server01

For more information about the Param statement and the function parameters,
see about_Functions and about_Functions_Advanced_Parameters.


You can write a help topic for a script by using either of the two following methods:

-- Comment-Based Help for Scripts

Create a Help topic by using special keywords in the comments. To create
comment-based Help for a script, the comments must be placed at the
beginning or end of the script file. For more information about
comment-based Help, see about_Comment_Based_Help.

-- XML-Based Help for Scripts

Create an XML-based Help topic, such as the type that is typically
created for cmdlets. XML-based Help is required if you are translating
Help topics into multiple languages.

To associate the script with the XML-based Help topic, use the
.ExternalHelp Help comment keyword. For more information about the
ExternalHelp keyword, see about_Comment_Based_Help. For more information
about XML-based help, see "How to Write Cmdlet Help" in the MSDN
(Microsoft Developer Network) library at


Each script runs in its own scope. The functions, variables, aliases, and
drives that are created in the script exist only in the script scope. You
cannot access these items or their values in the scope in which the
script runs.

To run a script in a different scope, you can specify a scope, such as
Global or Local, or you can dot source the script.

The dot sourcing feature lets you run a script in the current scope instead
of in the script scope. When you run a script that is dot sourced, the
commands in the script run as though you had typed them at the command
prompt. The functions, variables, aliases, and drives that the script
creates are created in the scope in which you are working. After the script
runs, you can use the created items and access their values in your session.

To dot source a script, type a dot (.) and a space before the script path.

For example:

. C:\scripts\UtilityFunctions.ps1


. .\UtilityFunctions.ps1

After the UtilityFunctions script runs, the functions and variables that the
script creates are added to the current scope.

For example, the UtilityFunctions.ps1 script creates the New-Profile
function and the $ProfileName variable.

#In UtilityFunctions.ps1

function New-Profile
Write-Host "Running New-Profile function"
$profileName = split-path $profile -leaf

if (test-path $profile)
{write-error "There is already a $profileName profile on this computer."}
{new-item -type file -path $profile -force }

If you run the UtilityFunctions.ps1 script in its own script scope, the
New-Profile function and the $ProfileName variable exist only while the
script is running. When the script exits, the function and variable are
removed, as shown in the following example.

C:\PS> .\UtilityFunctions.ps1

C:\PS> New-Profile
The term 'new-profile' is not recognized as a cmdlet, function, operable
program, or script file. Verify the term and try again.
At line:1 char:12
+ new-profile <<<<
+ CategoryInfo : ObjectNotFound: (new-profile:String) [],
+ FullyQualifiedErrorId : CommandNotFoundException

C:\PS> $profileName

When you dot source the script and run it, the script creates the
New-Profile function and the $ProfileName variable in your session in your
scope. After the script runs, you can use the New-Profile function in your
session, as shown in the following example.

C:\PS> . .\UtilityFunctions.ps1

C:\PS> New-Profile

Directory: C:\Users\juneb\Documents\WindowsPowerShell

Mode LastWriteTime Length Name
---- ------------- ------ ----
-a--- 1/14/2009 3:08 PM 0 Microsoft.PowerShellISE_profile.ps1

C:\PS> $profileName

For more information about scope, see about_Scopes.


A module is a set of related Windows PowerShell resources that can be
distributed as a unit. You can use modules to organize your scripts,
functions, and other resources. You can also use modules to distribute your
code to others, and to get code from trusted sources.

You can include scripts in your modules, or you can create a script module,
which is a module that consists entirely or primarily of a script and
supporting resources. A script module is just a script with a .psm1 file
name extension.

For more information about modules, see about_Modules.


Windows PowerShell has many useful features that you can use in scripts.

You can use a #Requires statement to prevent a script from running
without specified modules or snap-ins and a specified version of
Windows PowerShell. For more information, see about_Requires.

Contains the full path and name of the script that is being run.
This parameter is valid in all scripts. This automatic variable is
introduced in Windows PowerShell 3.0.

Contains the directory from which a script is being run. In
Windows PowerShell 2.0, this variable is valid only in script modules
(.psm1). Beginning in Windows PowerShell 3.0, it is valid in all scripts.

The $MyInvocation automatic variable contains information about the
current script, including information about how it was started or
"invoked." You can use this variable and its properties to get
information about the script while it is running. For example, the
$MyInvocation.MyCommand.Path variable contains the path and file name
of the script. $MyInvocation.Line contains the command that started
the script, including all parameters and values.

Beginning in Windows PowerShell 3.0, $MyInvocation has two new properties
that provide information about the script that called or invoked the
current script. The values of these properties are populated only when
the invoker or caller is a script.

-- PSCommandPath contains the full path and name of the script that called
or invoked the current script.
-- PSScriptRoot contains the directory of the script that called or invoked
the current script.

Unlike the $PSCommandPath and $PSScriptRoot automatic variables, which
contain information about the current script, the PSCommandPath and
PSScriptRoot properties of the $MyInvocation variable contain information
about the script that called or invoke the current script.

Data sections
You can use the Data keyword to separate data from logic in scripts.
Data sections can also make localization easier. For more information,
see about_Data_Sections and about_Script_Localization.

Script Signing
You can add a digital signature to a script. Depending on the execution
policy, you can use digital signatures to restrict the running of scripts
that could include unsafe commands. For more information, see
about_Execution_Policies and about_Signing.