CA and Code Signing Scripts in PS Core 6.1

Hi,

I have installed PS Core 6.1 on a new install of Win10. I want to know the correct way to install a cert and sign scripts that i download.
What are the best practices in Test and Production?
I have had a look around the internet and some places say to use makecert.exe but then it says it has been deprecated and to use the PS Cmdlet New-SelfSignedCertificate but this does not work in PS Core 6.1? Do I need to import this or is there a better way? I also have a Windows Domain environment.

If you are on a Windows box, PS Win and PSCore (PSv6) are installed side-by-side. This is by design as they are two different things. So, you’d use PSWIn for all things PSCode can’t do, and use PSCore for all the things it does and or does better than PSWin.

Why are you looking to use a self-signed cert, especially if this is an enterprise operational thing, vs a domain CA issued cert?
The New-SelefSignedCertificate cmdlet is simply not available on PSv6. Not all cmdlets are available across all versions of PS. Some are even only available on certain OS versions, even on Windows.

Makecert.exe works just fine, depreciated or not and makecert.exe is avaialbe on PS6 installs as long as you have it on your system.

PowerShell v6.0.2
Copyright (c) Microsoft Corporation. All rights reserved.

https://aka.ms/pscore6-docs
Type 'help' to get help.

PS C:\Program Files\PowerShell\6.0.2> Get-Command -Name '*cert*'

CommandType     Name                                               Version    Source
-----------     ----                                               -------    ------
Cmdlet          Get-PfxCertificate                                 3.0.0.0    Microsoft.PowerShell.Security
Application     appidcertstorecheck.exe                            10.0.17... C:\WINDOWS\system32\appidcertstorecheck.exe
Application     CertEnrollCtrl.exe                                 10.0.17... C:\WINDOWS\system32\CertEnrollCtrl.exe
Application     certlm.msc                                         0.0.0.0    C:\WINDOWS\system32\certlm.msc
Application     certmgr.msc                                        0.0.0.0    C:\WINDOWS\system32\certmgr.msc
Application     certreq.exe                                        10.0.17... C:\WINDOWS\system32\certreq.exe
Application     certutil.exe                                       10.0.17... C:\WINDOWS\system32\certutil.exe
Application     dmcertinst.exe                                     10.0.17... C:\WINDOWS\system32\dmcertinst.exe
Application     makecert.exe                                       6.1.760... C:\Users\Daniel\AppData\Local\Programs\Fiddler\makecert.exe
Application     TRACERT.EXE                                        10.0.17... C:\WINDOWS\system32\TRACERT.EXE
Application     TrustCert.exe                                      1.0.5.0    C:\Users\Daniel\AppData\Local\Programs\Fiddler\TrustCert.exe

Importing a cert, is just a matter of adding it to the user certificate store for use.
So, you do that manually via the MMC or certutil.exe or the Import-* cmdlets via PSWin.

 Get-Command -Name '*import*cert*'

CommandType     Name                                               Version    Source
-----------     ----                                               -------    ------
Cmdlet          Import-ACMCertificate                              3.3.234.0  AWSPowerShell
Cmdlet          Import-AzureKeyVaultCertificate                    4.1.0      AzureRM.KeyVault
Cmdlet          Import-AzureRmApiManagementHostnameCertificate     5.1.0      AzureRM.ApiManagement
Cmdlet          Import-Certificate                                 1.0.0.0    PKI
Cmdlet          Import-DMSCertificate                              3.3.234.0  AWSPowerShell
Cmdlet          Import-PfxCertificate                              1.0.0.0    PKI

Then you have the pre-made script via the MS TechNet and the MS powershellgallery.com

Self-signed certificate generator (PowerShell)

This script is an enhanced open-source PowerShell implementation of deprecated makecert.exe tool and utilizes the most modern certificate API — CertEnroll

Browse code samples | Microsoft Learn

Carbon 2.5.4

Carbon is a PowerShell module for automating the configuration Windows 7, 8, 2008, and 2012 and automation the installation and configuration of Windows applications, websites, and services. It can configure and manage:

Get-Certificate
Get-CertificateStore
Install-Certificate
Uninstall-Certificate

PowerShell Gallery | Carbon 2.5.4

Signing PowerShell Scripts (Self-Signed)

hanselman.com/blog/SigningPowerShellScripts.aspx

Hey, Scripting Guy! How Can I Sign Windows PowerShell Scripts with an Enterprise Windows PKI?

Hey, Scripting Guy! How Can I Sign Windows PowerShell Scripts with an Enterprise Windows PKI? (Part 1 of 2) - Scripting Blog [archived]

Hey, Scripting Guy! How Can I Sign Windows PowerShell Scripts with an Enterprise Windows PKI? (Part 2 of 2) - Scripting Blog [archived]

Thanks for clarifying this.
I wanted to use the self signed cert in a test environment.
I also use Linux. Powershell has automatically upgraded to PS Core so how can i run PS Standard on linux?