Invoke-RestMethod - Ignore Self Signed Certs

This will also work in later versions of powershell with invoke-restmethod/webrequest. It avoids the requirement for a runspace by implementing the handler as native .net:

if (-not("dummy" -as [type])) {    add-type -TypeDefinition @"using System;using System.Net;using System.Net.Security;using System.Security.Cryptography.X509Certificates;public static class Dummy {    public static bool ReturnTrue(object sender,        X509Certificate certificate,        X509Chain chain,        SslPolicyErrors sslPolicyErrors) { return true; }    public static RemoteCertificateValidationCallback GetDelegate() {        return new RemoteCertificateValidationCallback(Dummy.ReturnTrue);    }}"@}[System.Net.ServicePointManager]::ServerCertificateValidationCallback = [dummy]::GetDelegate()

Hope this helps.

If after @x0n answer, you still have the problem, try add before Request/Rest this

[System.Net.ServicePointManager]::SecurityProtocol =[System.Net.SecurityProtocolType]::Tls12

Working script for me:

if (-not ([System.Management.Automation.PSTypeName]'ServerCertificateValidationCallback').Type){$certCallback = @"    using System;    using System.Net;    using System.Net.Security;    using System.Security.Cryptography.X509Certificates;    public class ServerCertificateValidationCallback    {        public static void Ignore()        {            if(ServicePointManager.ServerCertificateValidationCallback ==null)            {                ServicePointManager.ServerCertificateValidationCallback +=                     delegate                    (                        Object obj,                         X509Certificate certificate,                         X509Chain chain,                         SslPolicyErrors errors                    )                    {                        return true;                    };            }        }    }"@    Add-Type $certCallback }[System.Net.ServicePointManager]::SecurityProtocol = [System.Net.SecurityProtocolType]::Tls12;[ServerCertificateValidationCallback]::Ignore()Invoke-WebRequest https://*YOUR URI*

i know this is old, but it still came up when i had this question with out actually checking. google first right?

Try this:

invoke-restMethod -SkipCertificateCheck -uri 'https://server:4443/login' -etc..etc..etc..

got it here via google: https://docs.microsoft.com/en-us/powershell/module/microsoft.powershell.utility/invoke-restmethod?view=powershell-6