How to enable execution of PowerShell scripts?

Question

When I try to execute my PowerShell script I get this error:

File C:\Common\Scripts\hello.ps1 cannot be loaded because the execution of scripts is disabled on this system. Please see "get-help about_signing" for more details.
At line:1 char:13
+ .\hello.ps1 <<<<
+ CategoryInfo : NotSpecified: (:) [], PSSecurityException
+ FullyQualifiedErrorId : RuntimeException

Answer 1

1. Start Windows PowerShell with the "Run as Administrator" option. Only members of the Administrators group on the computer can change the execution policy.

2. Enable running unsigned scripts by entering:

   set-executionpolicy remotesigned
   

This will allow running unsigned scripts that you write on your local computer and signed scripts from Internet.

See also Running Scripts at Microsoft TechNet Library.

Answer 2

The Default Execution Policy is set to restricted, you can see it by typing:

Get-ExecutionPolicy

You should type the following to make it go to unrestricted mode:

Set-ExecutionPolicy unrestricted

Hope this helps

Answer 3

On my machine that I use to dev scripts, I will use -unrestricted as above. When deploying my scripts however, to an end user machine, I will just call powershell with the -executionpolicy switch:

powershell.exe -noprofile -executionpolicy bypass -file .\script.ps1

Answer 4

We can get the status of current ExecutionPolicy by the command below:

Get-ExecutionPolicy;

By default it is Restricted. To allow the execution of PowerShell Scripts we need to set this ExecutionPolicy either as Bypass or Unrestricted.

We can set the policy for Current User as Bypass or Unrestricted by using any of the below PowerShell command:

Set-ExecutionPolicy -Scope CurrentUser -ExecutionPolicy Bypass -Force;

Set-ExecutionPolicy -Scope CurrentUser -ExecutionPolicy Unrestricted -Force;

Unrestricted policy loads all configuration files and runs all scripts. If you run an unsigned script that was downloaded from the Internet, you are prompted for permission before it runs.

Whereas in Bypass policy, nothing is blocked and there are no warnings or prompts during script execution. Bypass ExecutionPolicy is more relaxed than Unrestricted.

Answer 5

Depending on the Windows version and configuration, you may have the following warning, even in Unrestricted mode:

Security warning
Run only scripts that you trust. While scripts from the internet can be useful, this
script can potentially harm your computer. If you trust this script, use the 
Unblock-File cmdlet to allow the script to run without this warning message. 
Do you want to run?
[D] Do not run  [R] Run once  [S] Suspend  [?] Help (default is "D")

The solution is to use the "bypass" policy, enabled with the following command:

Set-ExecutionPolicy Bypass

From the documentation:

Bypass: Nothing is blocked and there are no warnings or prompts.

This is obviously insecure, please understand the risks involved.

Answer 6

A reg key with:
Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows\PowerShell] "EnableScripts"=dword:00000001 "ExecutionPolicy"="Bypass"

and:

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows\PowerShell]
"EnableScripts"=dword:00000001 "ExecutionPolicy"="Unrestricted"

works indeed too.

Answer 7

For some reason the PowerShell cmdlet did not enable local execution globally, just for the local user context. If I tried to start a Powershell script from inside CygWin's bash prompt, for example, which runs under its own user context, it would not run, giving the "is not digitally signed" error. The answer was to go into the Local Group Policy Editor -> Local Computer Policy -> Administrative Templates -> Windows Components -> Windows PowerShell and double-click on 'Turn on Script Execution'. This then let me change it to 'Enabled' and then execution policy of "Allow local scripts and remote signed scripts" and have it work globally regardless of user context.

Answer 8

The accepted answer is right, but the policy modification is only available for the currently running instance of the Powershell, meaning once the instance of the Powershell is shut down. The policy will be reset. If a user reopens another instance of Powershell, the default policy will be applied which is Restricted

For me, I need to use the VisualStudio Code console and g++ from cygwin to build things. The console is using Powershell, with the default policy, nothing can be done. One solution is changing the policy everytime the console is fired in VisualStudio Code console, maybe a script of changing the policy.

I am lazy, so another solution is when I run the Powershell in admin mode, similar to what the accepted answer does. but with an extra parameter which changes values in the Registry table. Once it been done. Other instances of Powershell will use the RemoteSigned policy by default.

set-executionpolicy remotesigned -Scope CurrentUser

Answer 9

Setting the policy (correctly) is the best choice but on my managed systems I do not have the ability to change that policy.

For me, the simplest work-around to changing the policy is to open the script in the "PowerShell ISE", highlight the code (or part of the code) to execute and then click the "Run Selection" button (or use the F8 shortcut).

This is not the best solution & does little for automating tasks, but it does allow me the use & utility of PowerShell while not running afoul of my IS department.

Answer 10

The reason that the reg key works, is because it is doing exactly what the PS commands do. The commands write the changes to the reg keys. Commands are much quicker and easier than creating a reg key or digging into the registry.