When working with PowerShell on Windows, you might encounter an error message stating, "Não pode ser carregado porque a execução de scripts foi desabilitada neste sistema" (translated: "Cannot be loaded because script execution is disabled on this system"). This error occurs because PowerShell has a security feature that restricts the execution of scripts to prevent malicious activities. By default, the execution policy is set to "Restricted," which prevents any scripts from running.

In this article, I will guide you through the steps to change the execution policy to allow script execution in PowerShell.

Understanding PowerShell Execution Policies

PowerShell execution policies are a safety feature that controls the conditions under which PowerShell loads configuration files and runs scripts. There are several execution policies you can set:

• Restricted: No scripts can be run. PowerShell can be used only in interactive mode.
• AllSigned: Only scripts signed by a trusted publisher can be run.
• RemoteSigned: Downloaded scripts must be signed by a trusted publisher before they can be run.
• Unrestricted: No restrictions; all scripts can be run. However, you will be prompted for permission to run scripts downloaded from the internet.
• Bypass: Nothing is blocked and there are no warnings or prompts.
• Undefined: Removes the currently assigned execution policy from the current scope.

How to Change the Execution Policy

To change the execution policy, you need to use the Set-ExecutionPolicy cmdlet. Here’s how you can do it:

Step 1: Open PowerShell as Administrator

1. Click on the Start menu.
2. Type PowerShell.
3. Right-click on Windows PowerShell and select Run as Administrator.

Step 2: Check the Current Execution Policy

Before changing the execution policy, it’s a good practice to check the current policy. You can do this with the following command:

Get-ExecutionPolicy

Step 3: Change the Execution Policy

To change the execution policy to RemoteSigned, which is a common choice for allowing script execution while maintaining some security, use the following command:

Set-ExecutionPolicy RemoteSigned

You will be prompted to confirm the change. Type Y and press Enter.

Step 4: Verify the Change

After setting the new execution policy, verify it by running:

Get-ExecutionPolicy

This should return RemoteSigned.

Example: Running a PowerShell Script

Now that the execution policy is set to allow script execution, you can run PowerShell scripts. Here’s an example script that outputs "Hello, World!":

Create a new file named HelloWorld.ps1 with the following content:

Write-Output "Hello, World!"

To execute the script, navigate to the directory containing HelloWorld.ps1 and run:

.\HelloWorld.ps1

You should see "Hello, World!" printed in the PowerShell window.

Important Considerations

• Always be cautious when changing the execution policy, especially on production systems.
• Consider the security implications of allowing script execution and choose the policy that best fits your security requirements.
• Remember that execution policies are not a security system but a way to prevent accidental execution of scripts.