PowerShell ISE Clear Variables without restarting

PowerShell ISE and Variables values

This guide applies to Windows PowerShell ISE, which hosts Windows PowerShell rather than PowerShell 7. Microsoft maintains ISE for security and high-priority fixes but no longer develops new features. See Microsoft’s ISE overview.

Repeated runs in the same session can reuse state, particularly when code is dot-sourced or selected lines are executed in the console. Remove the variables owned by the script explicitly instead of deleting every writable variable in the session:

# Replace these example names with variables created by your script.
Remove-Variable -Name 'reportRows', 'targetServers' -ErrorAction SilentlyContinue

The original Remove-Variable * -ErrorAction SilentlyContinue command was too broad and did not clear all variables. System-owned and constant variables cannot be removed; silently suppressing errors also hides unsuccessful removals. See Remove-Variable.

PowerShell ISE Errors and Modules

You can clear the error collection before another test:

$error.Clear()

This only clears recorded errors. It does not repair the cause or reset the session.

Remove a specific module when you need to remove its exported commands:

# Replace with the module you are developing.
Remove-Module -Name 'MyAutomationModule' -ErrorAction SilentlyContinue

Remove-Module affects the current session, but it does not unload a module’s .NET assemblies. Removing all modules can also disrupt unrelated work.

Use a new process for an isolated test

Clearing variables, errors and modules does not produce a fresh ISE session. Loaded assemblies, other functions, background work and process-level state can remain. For a clean script run, start a separate process with no profile:

# Windows PowerShell 5.1; replace the example path.
powershell.exe -NoProfile -File 'C:\Scripts\MyScript.ps1'

# PowerShell 7, if installed and supported by the script.
pwsh -NoProfile -File 'C:\Scripts\MyScript.ps1'

A new process isolates in-memory PowerShell state; it does not undo changes to files, services or remote systems. For interactive ISE debugging that requires a clean process, close and reopen ISE.