Repro for 'Process.Start() loses identity when started from a Scheduled Task on Windows Server 2019'

If process-starter was started using impersonation (a scheduled task in this example), secure-operation will fail with Exception calling ".ctor" with "2" argument(s): "The specified network password is not correct.". This is strange, because if I start secure-operation directly in the scheduled task, it will execute it successfully.

Reproduction

Requirements

• OS: Windows Server 2019
• Powershell or Powershell Core

Steps

• Run:

git clone https://github.com/fhammerl/ps-task-repro.git

• Copy all ps1 files and key.pfx to C:\pstests - this folder is hardcoded in the scripts

• Run task-start-secureop-directly.ps1 and see it succeed. It will echo 'true' to success.txt. This proves that directly running the secure script from the task works.

• Run process-starter.ps1 and see it succeed. It will echo 'true' to success.txt. This proves that starting a new process without impersonation works.

• Run task-process-start-powershell and see it fail. It will echo Exception calling ".ctor" with "2" argument(s): "The specified network password is not correct.".' to errors.txt. This proves that executing a secure operation in a new process with impersonation fails.