PowerShell Output Freeze: Diagnosing and Fixing the Hanging Terminal Issue


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Many PowerShell users encounter situations where the terminal appears to hang, only to resume output after pressing Enter. This behavior isn't specific to any particular command or script - it can happen with native cmdlets, custom applications, or even simple logging scripts.

PowerShell uses a console buffer system that occasionally gets stuck in a wait state. The console host (conhost.exe) manages this buffer, and certain conditions can cause it to pause output processing:

# Example command that might demonstrate the issue
while ($true) {
    Write-Output "Continuous output $(Get-Date)"
    Start-Sleep -Seconds 1
}
  • Long-running processes with frequent output
  • Remote sessions (particularly over VPN)
  • When the console window loses and regains focus
  • During high system load conditions

1. Forcing Console Flush

Add explicit flush calls in your scripts:

[System.Console]::Out.Flush()
[System.Console]::Error.Flush()

2. Alternative Output Methods

Try using different output mechanisms:

# Using Write-Host instead of Write-Output
Write-Host "This output is less likely to get stuck"

3. Changing PowerShell Host Configuration

Modify your profile to adjust buffer settings:

$host.UI.RawUI.BufferSize = New-Object Management.Automation.Host.Size(2000, 9999)
$host.PrivateData.AutoFlush = $true

Use Sysinternals Process Monitor to analyze the hanging behavior:

# Filter for PowerShell process and console operations
# Look for WAIT operations on console handles

Add these registry tweaks to improve console behavior:

Windows Registry Editor Version 5.00

[HKEY_CURRENT_USER\Console]
"ForceV2"=dword:00000001
"LineWrap"=dword:00000001
"QuickEdit"=dword:00000001

Consider using more modern terminal alternatives:

  • Windows Terminal
  • ConEmu
  • FluentTerminal

Many PowerShell users encounter a frustrating scenario where the console suddenly stops displaying output until they press Enter. This isn't process-specific - it happens even with simple scripts that should output continuously. Let's examine why this occurs and how to resolve it.

The primary culprit is output buffering. PowerShell's console host buffers output differently than you might expect:


# Example script that might trigger the freeze
while ($true) {
    Write-Output "Current time: $(Get-Date)"
    Start-Sleep -Seconds 1
}

The buffer management can get stuck in these common scenarios:

  • Long-running processes with frequent output
  • Remote sessions (especially via SSH)
  • When piping output between commands
  • Certain console host configurations

Here are several approaches to prevent the freezing:

1. Force Flush the Buffer


# Using Out-Host to bypass buffering
while ($true) {
    "Current time: $(Get-Date)" | Out-Host
    Start-Sleep -Seconds 1
}

2. Change the Execution Policy


# Try running with -ExecutionPolicy Bypass
powershell.exe -ExecutionPolicy Bypass -File yourscript.ps1

3. Use Start-Transcript


Start-Transcript -Path "output.log"
# Your commands here
Stop-Transcript

For persistent issues, try adjusting console properties programmatically:


$host.UI.RawUI.BufferSize = New-Object Management.Automation.Host.Size(200, 3000)
$host.UI.RawUI.WindowSize = New-Object Management.Automation.Host.Size(200, 50)

If the issue persists, consider these alternatives:

  • Use PowerShell ISE or VS Code instead of the console
  • Redirect output to a file and monitor it separately
  • Try the newer Windows Terminal application