About PowerShell.exe

SHORT DESCRIPTION

Explains how to use the PowerShell.exe command-line tool. Displays the syntax and describes the command-line switches.

PowerShell.exe starts a PowerShell session. You can use it in Cmd.exe and in PowerShell.

LONG DESCRIPTION

SYNTAX

PowerShell[.exe]
    [-PSConsoleFile <file> | -Version <version>]
    [-NoLogo]
    [-NoExit]
    [-Sta]
    [-Mta]
    [-NoProfile]
    [-NonInteractive]
    [-InputFormat {Text | XML}]
    [-OutputFormat {Text | XML}]
    [-WindowStyle <style>]
    [-EncodedCommand <Base64EncodedCommand>]
    [-ConfigurationName <string>]
    [-File - | <filePath> <args>]
    [-ExecutionPolicy <ExecutionPolicy>]
    [-Command - | { <script-block> [-args <arg-array>] }
                | { <string> [<CommandParameters>] } ]

PowerShell[.exe] -Help | -? | /?

Parameters

-PSConsoleFile <FilePath>

Loads the specified PowerShell console file. Enter the path and name of the console file. To create a console file, use the Export-Console cmdlet in PowerShell.

-Version <PowerShell Version>

Starts the specified version of PowerShell. Valid values are 2.0 and 3.0. The version that you specify must be installed on the system. If Windows PowerShell 3.0 is installed on the computer, "3.0" is the default version. Otherwise, "2.0" is the default version. For more information, see Installing PowerShell.

Hides the copyright banner at startup.

-NoExit

Does not exit after running startup commands.

-Sta

Starts PowerShell using a single-threaded apartment. In Windows PowerShell 2.0, multi-threaded apartment (MTA) is the default. In Windows PowerShell 3.0, single-threaded apartment (STA) is the default.

-Mta

Starts PowerShell using a multi-threaded apartment. This parameter is introduced in PowerShell 3.0. In PowerShell 2.0, multi-threaded apartment (MTA) is the default. In PowerShell 3.0, single-threaded apartment (STA) is the default.

-NoProfile

Does not load the PowerShell profile.

-NonInteractive

Does not present an interactive prompt to the user.

-InputFormat {Text | XML}

Describes the format of data sent to PowerShell. Valid values are "Text" (text strings) or "XML" (serialized CLIXML format).

-OutputFormat {Text | XML}

Determines how output from PowerShell is formatted. Valid values are "Text" (text strings) or "XML" (serialized CLIXML format).

-WindowStyle <Window style>

Sets the window style for the session. Valid values are Normal, Minimized, Maximized and Hidden.

-EncodedCommand <Base64EncodedCommand>

Accepts a base-64-encoded string version of a command. Use this parameter to submit commands to PowerShell that require complex quotation marks or curly braces. The string must be formatted using UTF-16 character encoding.

-ConfigurationName <string>

Specifies a configuration endpoint in which PowerShell is run. This can be any endpoint registered on the local machine including the default PowerShell remoting endpoints or a custom endpoint having specific user role capabilities.

-File - | <filePath> <args>

If the value of File is "-", the command text is read from standard input. Running powershell -File - without redirected standard input starts a regular session. This is the same as not specifying the File parameter at all.

If the value of File is a file path, the script runs in the local scope ("dot-sourced"), so that the functions and variables that the script creates are available in the current session. Enter the script file path and any parameters. File must be the last parameter in the command. All values typed after the File parameter are interpreted as the script file path and parameters passed to that script.

Parameters passed to the script are passed as literal strings, after interpretation by the current shell. For example, if you are in cmd.exe and want to pass an environment variable value, you would use the cmd.exe syntax: powershell.exe -File .\test.ps1 -TestParam %windir%

In contrast, running powershell.exe -File .\test.ps1 -TestParam $env:windir in cmd.exe results in the script receiving the literal string $env:windir because it has no special meaning to the current cmd.exe shell. The $env:windir style of environment variable reference can be used inside a Command parameter, since there it will be interpreted as PowerShell code.

When the value of File is a file path, File must be the last parameter specified because any characters typed after the command are interpreted as the command arguments.

You can include the script parameters and values in the value of the File parameter. For example: -File .\Get-Script.ps1 -Domain Central

Typically, the switch parameters of a script are either included or omitted. For example, the following command uses the All parameter of the Get-Script.ps1 script file: -File .\Get-Script.ps1 -All

In rare cases, you might need to provide a Boolean value for a switch parameter. To provide a Boolean value for a switch parameter in the value of the File parameter, enclose the parameter name and value in curly braces, such as the following: -File .\Get-Script.ps1 {-All:$False}.

-ExecutionPolicy <ExecutionPolicy>

Sets the default execution policy for the current session and saves it in the $env:PSExecutionPolicyPreference environment variable. This parameter does not change the PowerShell execution policy that is set in the registry. For information about PowerShell execution policies, including a list of valid values, see about_Execution_Policies.

-Command

Executes the specified commands (with any parameters) as though they were typed at the PowerShell command prompt. After execution, PowerShell exits unless the NoExit parameter is specified. Any text after -Command is sent as a single command line to PowerShell. This is different from how -File handles parameters sent to a script.

The value of Command can be "-", a string, or a script block. The results of the command are returned to the parent shell as deserialized XML objects, not live objects.

If the value of Command is "-", the command text is read from standard input. You must redirect standard input when using the Command parameter with standard input. For example:

@'
"in"

"hi" |
  % { "$_ there" }

"out"
'@ | powershell -NoProfile -Command -

This example produces the following output:

in
hi there
out

When the value of Command is a string, Command must be the last parameter specified because any characters typed after the command are interpreted as the command arguments.

The Command parameter only accepts a script block for execution when it can recognize the value passed to Command as a ScriptBlock type. This is only possible when running PowerShell.exe from another PowerShell host. The ScriptBlock type may be contained in an existing variable, returned from an expression, or parsed by the PowerShell host as a literal script block enclosed in curly braces {}, before being passed to PowerShell.exe.

In cmd.exe, there is no such thing as a script block (or ScriptBlock type), so the value passed to Command will always be a string. You can write a script block inside the string, but instead of being executed it will behave exactly as though you typed it at a typical PowerShell prompt, printing the contents of the script block back out to you.

A string passed to Command will still be executed as PowerShell, so the script block curly braces are often not required in the first place when running from cmd.exe. To execute an inline script block defined inside a string, the call operator & can be used:

"& {<command>}"

-Help, -?, /?

Displays help for PowerShell.exe. If you are typing a PowerShell.exe command in a PowerShell session, prepend the command parameters with a hyphen (-), not a forward slash (/). You can use either a hyphen or forward slash in cmd.exe.

REMARKS

Troubleshooting note: In PowerShell 2.0, starting some programs from the PowerShell console fails with a LastExitCode of 0xc0000142.

EXAMPLES

# Create a new PowerShell session and load a saved console file
PowerShell -PSConsoleFile sqlsnapin.psc1

# Create a new PowerShell V2 session with text input, XML output, and no logo
PowerShell -Version 2.0 -NoLogo -InputFormat text -OutputFormat XML

# Execute a PowerShell Command in a session
PowerShell -Command "Get-EventLog -LogName security"

# Run a script block in a session
PowerShell -Command {Get-EventLog -LogName security}

# An alternate way to run a command in a new session
PowerShell -Command "& {Get-EventLog -LogName security}"

# To use the -EncodedCommand parameter:
$command = "dir 'c:\program files' "
$bytes = [System.Text.Encoding]::Unicode.GetBytes($command)
$encodedCommand = [Convert]::ToBase64String($bytes)
powershell.exe -encodedCommand $encodedCommand