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{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"PowerShell hangs when a WinCompat module import fails due to Core engine modules not being found in $PSHOME\\Modules","articleBody":"I've encountered an issue using PowerShell **v7.0.1 or higher** in a .NET Windows application.\r\nThis bug causes a hang when PS fails to import a module through WinCompat in these two scenarios:\r\n1. the application depends only on System.Management.Automation and Microsoft.PowerShell.Security (the latter is needed because of #14095) but **not on the entire PowerShell SDK**\r\n2. the application depends on the entire PowerShell SDK, but only in self-contained published builds\r\n\r\nPS: I know that applications using PowerShell should depend on the entire SDK and not just on System.Management.Automation, but in my case I have an application that only needs to run some commands on the machine and then operate on their output. The full SDK contains 20MB+ of dependencies that my application never uses and significantly bloat the distributable EXE.\r\n\r\n## Steps to reproduce\r\n\r\nThe simplest code that triggers the bug is the following:\r\n```csharp\r\nInitialSessionState sessionState = InitialSessionState.CreateDefault2();\r\nsessionState.ExecutionPolicy = ExecutionPolicy.Unrestricted;  // needed to make import work\r\nusing PowerShell pwsh = PowerShell.Create(sessionState);\r\npwsh.AddScript(\"Import-Module Dism -UseWindowsPowerShell\");\r\npwsh.Invoke();\r\nConsole.WriteLine(\"Script executed\");\r\n```\r\nI have a created a VS project (which can be [downloaded here](https://drive.google.com/file/d/118wAPM5LGOyI3RAdUAxrBN9E_KLjXIpL/view?usp=sharing)) that contains this code and a PublishProfile that can be used to reproduce the bug in the second scenario described above.\r\n\r\n**Important:** when removing the project dependency on Microsoft.PowerShell.SDK remember to remove the `bin` directory inside the project folder! Otherwise you'll get inconsistent results.\r\n\r\n## Expected behavior\r\n\r\n```\r\nScript executed\r\n```\r\nis printed to the standard output and then the application exits gracefully. (in scenario 1 `Import-Module` command will fail anyway, since we don't have `Microsoft.PowerShell.Utility` module that is required for WinCompat)\r\n\r\n## Actual behavior\r\n\r\nThe application hangs indefinitely before printing the `Script executed` message when:\r\n- it depends only on System.Management.Automation and Microsoft.PowerShell.Security v7.0.1+ regardless of the build type\r\n- it depends on Microsoft.PowerShell.SDK v7.0.1+, but **only in Published builds**\r\n\r\n### Possible cause\r\nLooking at the [stack trace of the pipeline execution thread](https://pastebin.com/uvQkdxZ0) while the application hangs in scenario 1, the thread appears to be stuck in an infinite loop when trying to import the `Microsoft.PowerShell.Utility` module.\r\nThis bug was introduced by #12269. (see my analysis below: https://github.com/PowerShell/PowerShell/issues/13157#issuecomment-741975648)","author":{"url":"https://github.com/Fs00","@type":"Person","name":"Fs00"},"datePublished":"2020-07-11T14:09:02.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":16},"url":"https://github.com/13157/PowerShell/issues/13157"}