Set-Execution Policy

Syntax

Set-ExecutionPolicy
   [-ExecutionPolicy] <ExecutionPolicy>
   [[-Scope] <ExecutionPolicyScope>]
   [-Force]
   [-WhatIf]
   [-Confirm]
   [<CommonParameters>]

Description

The Set-ExecutionPolicy cmdlet changes the user preference for the Windows PowerShell execution policy.

The execution policy is part of the security strategy of Windows PowerShell. It determines whether you can load configuration files (including your Windows PowerShell profile) and run scripts, and it determines which scripts, if any, must be digitally signed before they will run. For more information, see about_Execution_Policies ( http://go.microsoft.com/fwlink/?LinkID=135170 ).

To change the execution policy for the default (LocalMachine) scope, start Windows PowerShell with the "Run as administrator" option.

Examples

Example 1: Set the shell execution policy

PS C:\> Set-ExecutionPolicy -ExecutionPolicy RemoteSigned

This command sets the user preference for the shell execution policy to RemoteSigned.

Example 2: Set a shell execution policy that conflicts with the group policy

PS C:\> Set-ExecutionPolicy -ExecutionPolicy Restricted

Set-ExecutionPolicy : Windows PowerShell updated your local preference successfully, but the setting is

overridden by the group policy applied to your system. Due to the override, your shell will retain its current

effective execution policy of "AllSigned". Contact your group policy administrator for more information.

At line:1 char:20

+ Set-ExecutionPolicy  <<<< restricted

This command attempts to set the execution policy for the shell to Restricted. The Restricted setting is written to the registry, but because it conflicts with a group policy, it is not effective, even though it is more restrictive than the group policy.

Example 3: Apply the execution policy from a remote computer to the local computer

PS C:\> Invoke-Command -ComputerName "Server01" -ScriptBlock {Get-ExecutionPolicy} | Set-ExecutionPolicy -Force

This command gets the execution policy from a remote computer and applies that execution policy to the local computer.

The command uses the Invoke-Command cmdlet to send the command to the remote computer. Because you can pipe an ExecutionPolicy (Microsoft.PowerShell.ExecutionPolicy) object to Set-ExecutionPolicy , the Set-ExecutionPolicy command does not require an ExecutionPolicy parameter.

The command uses the Force parameter to suppress the user prompt.

Example 4: Set the scope for an execution policy

PS C:\> Set-ExecutionPolicy -Scope CurrentUser -ExecutionPolicy AllSigned -Force



The second command uses the *List* parameter of the Get-ExecutionPolicy cmdlet to get the execution policies set in each scope. The results show that the execution policy that is set for the current user differs from the execution policy set for all users of the computer.

PS C:\> Get-ExecutionPolicy -List

Scope            ExecutionPolicy

-----            ---------------

MachinePolicy    Undefined

UserPolicy       Undefined

Process          Undefined

CurrentUser      AllSigned

LocalMachine     RemoteSigned





PS C:\> Get-ExecutionPolicy

AllSigned

This example shows how to set an execution policy for a particular scope.

The first command uses the Set-ExecutionPolicy cmdlet to set an execution policy of AllSigned for the current user. It uses the Force parameter to suppress the user prompt.

Example 5: Remove the execution policy for the current user

PS C:\> Set-ExecutionPolicy -Scope CurrentUser -ExecutionPolicy Undefined

This command uses an execution policy value of Undefined to effectively remove the execution policy that is set for the current user scope. As a result, the execution policy that is set in Group Policy or in the LocalMachine (all users) scope is effective.

If you set the execution policy in all scopes to Undefined and the Group Policy is not set, the default execution policy, Restricted, is effective for all users of the computer.

Example 6: Set the execution policy for the current session

PS C:\> Set-ExecutionPolicy -Scope Process -ExecutionPolicy AllSigned

This command sets an execution policy of AllSigned for only the current Windows PowerShell session. This execution policy is saved in the PSExecutionPolicyPreference environment variable ($env:PSExecutionPolicyPreference), so it does not affect the value in the registry. The variable and its value are deleted when the current session is closed.

Example 7: Unblock a script to run it without changing the execution policy

The first command uses the **Set-ExecutionPolicy** cmdlet to change the execution policy to RemoteSigned.

PS C:\> Set-ExecutionPolicy -ExecutionPolicy RemoteSigned



The second command uses the Get-ExecutionPolicy cmdlet to get the effective execution policy in the session. The output shows that it is RemoteSigned.

PS C:\> Get-ExecutionPolicy

RemoteSigned



The third command shows what happens when you run a blocked script in a Windows PowerShell session in which the execution policy is RemoteSigned. The RemoteSigned policy prevents you from running scripts that are downloaded from the Internet unless they are digitally signed.

PS C:\> .\Start-ActivityTracker.ps1

.\Start-ActivityTracker.ps1 : File .\Start-ActivityTracker.ps1 cannot be loaded. The file .\Start-ActivityTracker.ps1

is not digitally signed. The script will not execute on the system. For more information, see about_Execution_Policies

at http://go.microsoft.com/fwlink/?LinkID=135170.

At line:1 char:1

+ .\Start-ActivityTracker.ps1

+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~

+ CategoryInfo          : NotSpecified: (:) [], PSSecurityException

+ FullyQualifiedErrorId : UnauthorizedAccess



The fourth command uses the Unblock-File cmdlet to unblock the script so it can run in the session.Before running an **Unblock-File** command, read the script contents and verify that it is safe.

PS C:\> Unblock-File -Path "Start-ActivityTracker.ps1"



The fifth and sixth commands show the effect of the **Unblock-File** command. The **Unblock-File** command does not change the execution policy. However, it unblocks the script so it will run in Windows PowerShell.

PS C:\> Get-ExecutionPolicy

RemoteSigned

PS C:\> Start-ActivityTracker.ps1

Task 1:

This example shows the effect of the RemoteSigned execution policy, which prevents you from running unsigned scripts that were downloaded from the Internet. It also shows how to use the Unblock-File cmdlet to unblock scripts, so that you can run them without changing the execution policy.

Required Parameters

Optional Parameters

Inputs

Microsoft.PowerShell.ExecutionPolicy, System.String

You can pipe an execution policy object or a string that contains the name of an execution policy to Set-ExecutionPolicy .

Outputs

None

This cmdlet does not return any output.

Notes

• When you use Set-ExecutionPolicy in any scope other than Process, the new user preference is saved in the registry and remains unchanged until you change it. When the value of the Scope parameter is Process, the user preference is stored in the PSExecutionPolicyPreference environment variable ($env:PSExecutionPolicyPreference), instead of the registry, and it is deleted when the session in which it is effective is closed.

  If the "Turn on Script Execution" group policy is enabled for the computer or user, the user preference is saved, but it is not effective, and Windows PowerShell displays a message explaining the conflict. You cannot use Set-ExecutionPolicy to override a Group Policy, even if the user preference is more restrictive than the policy.

*

Related Links

• Get-AuthenticodeSignature
• Get-ExecutionPolicy
• Set-AuthenticodeSignature