Error starting PowerShell 7.4.0+

[giggio]

Prerequisites

• Write a descriptive title.
• Make sure you are able to repro it on the latest released version
• Search the existing issues.
• Refer to the FAQ.
• Refer to Differences between Windows PowerShell 5.1 and PowerShell.

Steps to reproduce

1. Install PowerShell 7.4.0
2. Start it
3. Create a powershell.config.json and set PSModulePath to multiple paths, separated by ; (path separator char) (see reference).
4. See it fail

Expected behavior

It starts, like 7.3 did.

Actual behavior

It fails with:

PowerShell 7.4.0
The shell cannot be started. A failure occurred during initialization:
Index was out of range. Must be non-negative and less than or equal to the size of the collection. (Parameter 'startIndex')

Error details

Not possible.

Environment data

Not possible, but it is version 7.4.0.

Visuals

This is starting from Nushell:

This is starting it from Windows Terminal:

Additional context

Downloaded and installed this file: https://github.com/PowerShell/PowerShell/releases/download/v7.4.0/PowerShell-7.4.0-win-x64.msi

I debugged and found out that the exception is ocurring at this location (ModuleIntrinsics.UpdatePath):

PowerShell/src/System.Management.Automation/engine/Modules/ModuleIntrinsics.cs

Line 1278 in ad2bf78

insertIndex = path.IndexOf(Path.PathSeparator, PathContainsSubstring(path, pathToAdd));

The arguments for UpdatePath are:
path: a string with a ; separated list of paths
pathToAdd: another string with a ; separated list of paths
insertIndex: 0

The call that is failing is the one to path.IndexOf, which is passed ; and -1 (which is the result from the call to PathContainsSubstring).

The problem only happens because pathToAdd has several paths with the ; separator. If it was a single path without ; it would work.

The issue seems to have been introduced in commit 3710671.

[rhubarb-geek-nz]

Can you check with "Add or Remove programs" settings that there is only one PowerShell MSI installed, and you don't have both 7.3.9 and 7.4.0?

The reason I say that is I found I had both installed, one with a normal MSI icon, the other with a PowerShell icon.

[giggio]

@rhubarb-geek-nz I did, I hadn't.

[B-Art]

There are at least 4 ways to install Pwsh on Windows:
From MSStore, via MSI, via Winget and Unzipping the download.
Which one did you use @giggio ?
https://learn.microsoft.com/en-us/powershell/scripting/install/installing-powershell-on-windows?view=powershell-7.4

[giggio]

First I tried via winget. Then via the MSI download. Same result.

[rhubarb-geek-nz]

First I tried via winget. Then via the MSI download. Same result.

Have you tried completely uninstalling the previous MSI first? Not ideal I know, in-place updates should work. Use "Add or Remove programs" to see what is installed, and also check the directory "c:\Program Files\PowerShell\7"

[giggio]

Have you tried completely uninstalling the previous MSI first? Not ideal I know, in-place updates should work. Use "Add or Remove programs" to see what is installed, and also check the directory "c:\Program Files\PowerShell\7"

I have.

I have now also tried installing the Microsoft Store Version, and I get the same error:

[giggio]

Tried now using the global tool, it also does not work:

I installed 7.3.10, as it still works. :(

[rhubarb-geek-nz]

Alas, there are enough other problems with 7.4.0 to suggest sticking with 7.3.10 ( for the moment ).

[giggio]

The problem persists at version 7.4.1, released more recently.

[giggio]

Also, tried using version 7.5 preview from the store, also broken.

[giggio]

I have tracked the error and added the explanation of why it is happening to the additional context section of the issue.

[Alvaka-KThor]

I am also experiencing this issue. I've had to use PSModulePath environment variable within System Properties in the meantime, which is not a perfect workaround.

[w-boyd]

On Linux:

ForEach-Object: /home/vsts/work/_temp/f3a905a8-4984-469a-b3ba-7a9ba49e76af.ps1:5
Line |
   5 |  "whatever" | ForEach-Object -Parallel { $_ }
     |               ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     | An unexpected error has occurred while processing ForEach-Object
     | -Parallel input. This may mean that some of the piped input did not get
     | processed. Error: System.ArgumentOutOfRangeException: Index was out of
     | range. Must be non-negative and less than or equal to the size of the
     | collection. (Parameter 'startIndex')    at System.String.IndexOf(Char
     | value, Int32 startIndex, Int32 count)    at
     | System.Management.Automation.ModuleIntrinsics.UpdatePath(String path,
     | String pathToAdd, Int32& insertIndex)    at
     | System.Management.Automation.ModuleIntrinsics.GetModulePath(String
     | currentProcessModulePath, String hklmMachineModulePath, String
     | hkcuUserModulePath)    at
     | System.Management.Automation.ModuleIntrinsics.SetModulePath()    at
     | System.Management.Automation.ModuleIntrinsics..ctor(ExecutionContext
     | context)    at
     | System.Management.Automation.ExecutionContext.InitializeCommon(AutomationEngine engine, PSHost hostInterface)    at System.Management.Automation.AutomationEngine..ctor(PSHost hostInterface, InitialSessionState iss)    at System.Management.Automation.Runspaces.LocalRunspace.DoOpenHelper()    at System.Management.Automation.Runspaces.RunspaceBase.CoreOpen(Boolean syncCall)    at System.Management.Automation.PSTasks.PSTaskPool.GetRunspace(Int32 taskId)    at System.Management.Automation.PSTasks.PSTaskPool.Add(PSTaskBase task)    at Microsoft.PowerShell.Commands.ForEachObjectCommand.<InitParallelParameterSet>b__67_2(Object _).

On Windows:

"C:\Program Files\PowerShell\7\pwsh.exe" -NoLogo -NoProfile -NonInteractive -ExecutionPolicy Unrestricted -Command ". 'D:\a\_temp\86498521-8914-4ea7-ba0c-67b8bb7a6633.ps1'"
The shell cannot be started. A failure occurred during initialization:
Index was out of range. Must be non-negative and less than or equal to the size of the collection. (Parameter 'startIndex')
##[error]PowerShell exited with code '70'.

Azure DevOps pipeline yaml to reproduce the issue:

jobs:
- job: windows
  pool:
      vmImage: windows-latest
  steps:
  - pwsh: |
      $filePath = Join-Path $env:SYSTEM_DEFAULTWORKINGDIRECTORY "powershellmodules"
      $separator = $isWindows ? ";" : ":"   
      $updatedPSModulePath = $env:PSModulePath, $filePath -join $separator
      $powershellConfigPath = Join-Path $PSHOME 'powershell.config.json'
      if (-not (Test-Path $powershellConfigPath)){
        New-Item -Path $powershellConfigPath -ItemType File -Force
        $config = @{
          PSModulePath = $updatedPSModulePath
        }
      }
      else {
        Write-Verbose "Found existing powershell config, updating PSModulePath"
        $config = Get-Content -Path $powershellConfigPath | ConvertFrom-Json -AsHashtable -Depth 100
        $config["PSModulePath"] = $updatedPSModulePath
      }
      Write-Verbose "Pushing content to $powershellConfigPath" -Verbose
      $config | ConvertTo-Json -Depth 100 | Tee-Object -FilePath $powershellConfigPath
    displayName: Update PSModulePath

  - pwsh: |
      Write-Verbose ('$env:PSModulePath {0}' -f $env:PSModulePath) -Verbose
      "whatever" | ForEach-Object -Parallel { $_ }
    displayName: Debug

- job: linux
  pool:
      vmImage: ubuntu-latest
  steps:
  - pwsh: |
      $filePath = Join-Path $env:SYSTEM_DEFAULTWORKINGDIRECTORY "powershellmodules"
      $separator = $isWindows ? ";" : ":"   
      $updatedPSModulePath = $env:PSModulePath, $filePath -join $separator
      $powershellConfigPath = Join-Path $PSHOME 'powershell.config.json'
      if (-not (Test-Path $powershellConfigPath)){
        New-Item -Path $powershellConfigPath -ItemType File -Force
        $config = @{
          PSModulePath = $updatedPSModulePath
        }
      }
      else {
        Write-Verbose "Found existing powershell config, updating PSModulePath"
        $config = Get-Content -Path $powershellConfigPath | ConvertFrom-Json -AsHashtable -Depth 100
        $config["PSModulePath"] = $updatedPSModulePath
      }
      Write-Verbose "Pushing content to $powershellConfigPath" -Verbose
      $config | ConvertTo-Json -Depth 100 | Tee-Object -FilePath $powershellConfigPath
    displayName: Update PSModulePath

  - pwsh: |
      Write-Verbose ('$env:PSModulePath {0}' -f $env:PSModulePath) -Verbose
      "whatever" | ForEach-Object -Parallel { $_ }
    displayName: Debug

[wboyd-aw]

Any updates?

[hoffmanntravis]

I have reproduced this issue on Powershell 7.4.6 locally. This works:

{
    "PSModulePath": ":"
}

This does not:

{
    "PSModulePath": ";"
}

File Path:
C:\Users<user>\Documents\PowerShell\powershell.config.json

This seems like a clear case of regression. Please investigate and fix.

[hoffmanntravis]

Couple more notes. This is still broken in Powershell Preview 7.5:

PowerShell 7.5.0-preview.5
The shell cannot be started. A failure occurred during initialization:
Index was out of range. Must be non-negative and less than or equal to the size of the collection. (Parameter 'startIndex')

[process exited with code 70 (0x00000046)]
You can now close this terminal with Ctrl+D, or press Enter to restart.

Also, note that in the example I listed in my last comment, the semicolon delimiter by itself alone is enough to break the startup of powershell.

According to this document, ; should be the delimiting character:
https://learn.microsoft.com/en-us/powershell/module/microsoft.powershell.core/about/about_psmodulepath?view=powershell-7.4#modifying-psmodulepath

Editing the config file is described here:
https://learn.microsoft.com/en-us/powershell/module/microsoft.powershell.core/about/about_powershell_config?view=powershell-7.4#psmodulepath

about_PSModulePath - PowerShell

The PSModulePath environment variable contains a list of folder locations that are searched to find modules and resources.

about_PowerShell_Config - PowerShell

Configuration files for PowerShell, replacing Registry configuration.

[jborean93]

Opened #24568 to fix this problem.