Fix individual commands that do not respect an explicit $false value passed to a switch parameter

Michael Klement (@mklement0)

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

# The *presence* of the switch selects UseWindowsPowerShellParameterSet.
# Irrespective of the switch *value*, CreateRunspacesForUseWindowsPowerShellParameterSet() is called.
# This subverts reasonable user expectation. UseWindowsPowerShell was NOT requested, yet the command
# ignores that request.
New-PSSession -UseWindowsPowerShell:$false

# Likewise, this results in [datetime] output, despite it not being requested.
$params = @{ Since = $false }
Get-Uptime @params

Context:

This is a continuation of the following issues:

Summary:

The first issue discusses how Get-Uptime -Since:$false is not respected. That is, despite the explicit $false value, Get-Uptime behaves as if -Since or -Since:$true was specified.
- This behavior was deemed erroneous and the issue was labelled Up-for-grabs.
The second issue is a proposal by Michael Klement (@mklement0) for a systematic change that would implicitly fix the Get-Uptime issue and other commands that exhibit the same problem.
- This proposal was rejected due to backwards compatibility concerns.
I encountered at least 10 commands shipped with PowerShell that exhibit the same problem when looking into the issue further. See here.
Per Ilya (@iSazonov) in #25015:

Up-for-Grabs - we should fix all cmdlets in the repo if they implement a switch in wrong way.

List of commands to fix:

Request

Fix each command listed above individually, so that explicitly passing a $false value to the specified switch parameter is respected.

Expected behavior

-Switch:$false results in the same behavior as not passing -Switch.

Actual behavior

For the commands listed above, -Switch:$false results in the same behavior as -Switch or -Switch:$true.

Environment data

Name                           Value
----                           -----
PSVersion                      7.6.0-preview.3
PSEdition                      Core
GitCommitId                    7.6.0-preview.3
OS                             Microsoft Windows 10.0.19045
Platform                       Win32NT
PSCompatibleVersions           {1.0, 2.0, 3.0, 4.0, 5.0, 5.1…}
PSRemotingProtocolVersion      2.3
SerializationVersion           1.1.0.1
WSManStackVersion              3.0

Ilya (@iSazonov)

Ilya (@iSazonov) Are individual issues for each of the affected commands also required? Or will this singular, meta-issue suffice?

Single issues & are linked to this one please. This allows smaller easier to review commits/PR's whilst enabling more than 1 person to work on fixing these issues at a time. It also helps the WG's when reviewing issues/PR's to be able to quickly review them if it's a smaller change.

Thanks, sounds good. I will link the new issues in the OP as and when they're submitted.

@PowerShell/wg-powershell-cmdlets agree these are bugs

I've removed Register-PSResourceRepository -PSGallery from the OP as it pertains to a command in a different repo.

Here's the PSResourceGet issue: PowerShell/PSResourceGet#1805

Are there other cases in our code base for fixing?

Are there other cases in our code base for fixing?

The original list in the OP is based on the testing here. I focused on all mandatory switch parameters belonging to commands shipped with PowerShell.

For non-mandatory, at the very least, we'd need to check parameters that meet the following criteria:

Belongs to a command from this repo (not already fixed in this issue).
Is a switch parameter (not common).
Belongs to a parameter set that isn't __AllParameterSets.

There's 137 parameters that meet that. Checking those would cover the most common cause of the issue (i.e., branching on the parameter set name instead of the switch value).

Parameter list to check:

Command                    Parameter                        Source                           InParameterSet
-------                    ---------                        ------                           --------------
Add-Member                 Force                            Microsoft.PowerShell.Utility     MemberSet, NotePropertySingleMemberSet, NotePropertyMultiMemberSet
Add-Member                 PassThru                         Microsoft.PowerShell.Utility     MemberSet, TypeNameSet, NotePropertySingleMemberSet, NotePropertyMultiMemberSet
Add-Type                   IgnoreWarnings                   Microsoft.PowerShell.Utility     FromSource, FromMember, FromPath, FromLiteralPath
Connect-PSSession          AllowRedirection                 Microsoft.PowerShell.Core        ConnectionUri, ConnectionUriGuid
Connect-PSSession          UseSSL                           Microsoft.PowerShell.Core        ComputerName, ComputerNameGuid
Connect-WSMan              UseSSL                           Microsoft.WSMan.Management       ComputerName
ConvertFrom-Csv            UseCulture                       Microsoft.PowerShell.Utility     UseCulture
ConvertFrom-SecureString   AsPlainText                      Microsoft.PowerShell.Security    AsPlainText
ConvertTo-Csv              UseCulture                       Microsoft.PowerShell.Utility     UseCulture
ConvertTo-Html             Fragment                         Microsoft.PowerShell.Utility     Fragment
ConvertTo-Html             Transitional                     Microsoft.PowerShell.Utility     Page
ConvertTo-SecureString     AsPlainText                      Microsoft.PowerShell.Security    PlainText
ConvertTo-SecureString     Force                            Microsoft.PowerShell.Security    PlainText
Enable-RunspaceDebug       BreakAll                         Microsoft.PowerShell.Utility     RunspaceParameterSet, RunspaceNameParameterSet, RunspaceIdParameterSet
Enter-PSSession            EnableNetworkAccess              Microsoft.PowerShell.Core        ComputerName, Uri
Enter-PSSession            RunAsAdministrator               Microsoft.PowerShell.Core        ContainerId
Enter-PSSession            UseSSL                           Microsoft.PowerShell.Core        ComputerName
Enter-PSSession            AllowRedirection                 Microsoft.PowerShell.Core        Uri
Enter-PSSession            SSHTransport                     Microsoft.PowerShell.Core        SSHHost
Export-Csv                 UseCulture                       Microsoft.PowerShell.Utility     UseCulture
ForEach-Object             AsJob                            Microsoft.PowerShell.Core        ParallelParameterSet
ForEach-Object             UseNewRunspace                   Microsoft.PowerShell.Core        ParallelParameterSet
Format-Hex                 Raw                              Microsoft.PowerShell.Utility     ByInputObject
Get-CimInstance            KeyOnly                          CimCmdlets                       ClassNameComputerSet, ClassNameSessionSet, ResourceUriComputerSet, ResourceUriSessionSet
Get-CimInstance            Shallow                          CimCmdlets                       ClassNameComputerSet, ClassNameSessionSet, ResourceUriSessionSet, ResourceUriComputerSet, QueryComputerSet, QuerySessionSet
Get-Command                UseFuzzyMatching                 Microsoft.PowerShell.Core        AllCommandSet
Get-Command                UseAbbreviationExpansion         Microsoft.PowerShell.Core        AllCommandSet
Get-Counter                Continuous                       Microsoft.PowerShell.Diagnostics GetCounterSet
Get-Culture                NoUserOverrides                  Microsoft.PowerShell.Utility     CurrentCulture, Name
Get-Culture                ListAvailable                    Microsoft.PowerShell.Utility     ListAvailable
Get-Help                   Detailed                         Microsoft.PowerShell.Core        DetailedView
Get-Help                   Full                             Microsoft.PowerShell.Core        AllUsersView
Get-Help                   Examples                         Microsoft.PowerShell.Core        Examples
Get-Help                   Online                           Microsoft.PowerShell.Core        Online
Get-Help                   ShowWindow                       Microsoft.PowerShell.Core        ShowWindow
Get-Job                    IncludeChildJob                  Microsoft.PowerShell.Core        SessionIdParameterSet, InstanceIdParameterSet, NameParameterSet, StateParameterSet, CommandParameterSet
Get-Location               Stack                            Microsoft.PowerShell.Management  Stack
Get-Module                 All                              Microsoft.PowerShell.Core        Loaded, Available
Get-Module                 ListAvailable                    Microsoft.PowerShell.Core        Available, PsSession, CimSession
Get-Module                 SkipEditionCheck                 Microsoft.PowerShell.Core        Available, PsSession, CimSession
Get-Module                 Refresh                          Microsoft.PowerShell.Core        Available, PsSession, CimSession
Get-Process                IncludeUserName                  Microsoft.PowerShell.Management  NameWithUserName, IdWithUserName, InputObjectWithUserName
Get-Process                Module                           Microsoft.PowerShell.Management  Name, Id, InputObject
Get-Process                FileVersionInfo                  Microsoft.PowerShell.Management  Name, Id, InputObject
Get-PSSession              AllowRedirection                 Microsoft.PowerShell.Core        ConnectionUri, ConnectionUriInstanceId
Get-PSSession              UseSSL                           Microsoft.PowerShell.Core        ComputerName, ComputerInstanceId
Get-Unique                 AsString                         Microsoft.PowerShell.Utility     AsString
Get-Unique                 OnType                           Microsoft.PowerShell.Utility     UniqueByType
Get-WinEvent               Force                            Microsoft.PowerShell.Diagnostics ListLogSet, GetProviderSet, GetLogSet, HashQuerySet
Get-WinEvent               Oldest                           Microsoft.PowerShell.Diagnostics FileSet, GetProviderSet, GetLogSet, HashQuerySet, XmlQuerySet
Get-WSManInstance          BasePropertiesOnly               Microsoft.WSMan.Management       Enumerate
Get-WSManInstance          Enumerate                        Microsoft.WSMan.Management       Enumerate
Get-WSManInstance          Associations                     Microsoft.WSMan.Management       Enumerate
Get-WSManInstance          Shallow                          Microsoft.WSMan.Management       Enumerate
Get-WSManInstance          UseSSL                           Microsoft.WSMan.Management       GetInstance, Enumerate
Group-Object               AsHashTable                      Microsoft.PowerShell.Utility     HashTable
Group-Object               AsString                         Microsoft.PowerShell.Utility     HashTable
Import-Csv                 UseCulture                       Microsoft.PowerShell.Utility     CulturePath, CultureLiteralPath
Import-Module              SkipEditionCheck                 Microsoft.PowerShell.Core        Name, FullyQualifiedName, ModuleInfo, Assembly, PSSession, CimSession, FullyQualifiedNameAndPSSession
Import-Module              UseWindowsPowerShell             Microsoft.PowerShell.Core        WinCompat, FullyQualifiedNameAndWinCompat
Invoke-Command             UseSSL                           Microsoft.PowerShell.Core        ComputerName, FilePathComputerName
Invoke-Command             AsJob                            Microsoft.PowerShell.Core        ComputerName, Session, Uri, FilePathComputerName, FilePathRunspace, FilePathUri, VMId, VMName, ContainerId, FilePathVMId, FilePathVMName, FilePathContainerId, SSHHost, SSHHostHashParam, FilePathSSHHost, FilePathSSHHostHash
Invoke-Command             InDisconnectedSession            Microsoft.PowerShell.Core        ComputerName, FilePathComputerName, Uri, FilePathUri
Invoke-Command             HideComputerName                 Microsoft.PowerShell.Core        ComputerName, Session, Uri, FilePathComputerName, FilePathRunspace, FilePathUri, VMId, VMName, ContainerId, FilePathVMId, FilePathVMName, FilePathContainerId, SSHHost, SSHHostHashParam, FilePathSSHHost, FilePathSSHHostHash
Invoke-Command             NoNewScope                       Microsoft.PowerShell.Core        InProcess
Invoke-Command             AllowRedirection                 Microsoft.PowerShell.Core        Uri, FilePathUri
Invoke-Command             EnableNetworkAccess              Microsoft.PowerShell.Core        ComputerName, FilePathComputerName, Uri, FilePathUri
Invoke-Command             RunAsAdministrator               Microsoft.PowerShell.Core        ContainerId, FilePathContainerId
Invoke-Command             SSHTransport                     Microsoft.PowerShell.Core        SSHHost, FilePathSSHHost
Invoke-Command             RemoteDebug                      Microsoft.PowerShell.Core        ComputerName, Session, Uri, FilePathComputerName, FilePathRunspace, FilePathUri, VMId, VMName, ContainerId, FilePathVMId, FilePathVMName, FilePathContainerId, SSHHost, SSHHostHashParam, FilePathSSHHost, FilePathSSHHostHash
Invoke-RestMethod          NoProxy                          Microsoft.PowerShell.Utility     CustomMethodNoProxy, StandardMethodNoProxy
Invoke-RestMethod          ProxyUseDefaultCredentials       Microsoft.PowerShell.Utility     StandardMethod, CustomMethod
Invoke-WebRequest          NoProxy                          Microsoft.PowerShell.Utility     CustomMethodNoProxy, StandardMethodNoProxy
Invoke-WebRequest          ProxyUseDefaultCredentials       Microsoft.PowerShell.Utility     StandardMethod, CustomMethod
Invoke-WSManAction         UseSSL                           Microsoft.WSMan.Management       ComputerName
Join-String                SingleQuote                      Microsoft.PowerShell.Utility     SingleQuote
Join-String                DoubleQuote                      Microsoft.PowerShell.Utility     DoubleQuote
Measure-Object             StandardDeviation                Microsoft.PowerShell.Utility     GenericMeasure
Measure-Object             Sum                              Microsoft.PowerShell.Utility     GenericMeasure
Measure-Object             AllStats                         Microsoft.PowerShell.Utility     GenericMeasure
Measure-Object             Average                          Microsoft.PowerShell.Utility     GenericMeasure
Measure-Object             Maximum                          Microsoft.PowerShell.Utility     GenericMeasure
Measure-Object             Minimum                          Microsoft.PowerShell.Utility     GenericMeasure
Measure-Object             Line                             Microsoft.PowerShell.Utility     TextMeasure
Measure-Object             Word                             Microsoft.PowerShell.Utility     TextMeasure
Measure-Object             Character                        Microsoft.PowerShell.Utility     TextMeasure
Measure-Object             IgnoreWhiteSpace                 Microsoft.PowerShell.Utility     TextMeasure
New-CimInstance            ClientOnly                       CimCmdlets                       ClassNameSessionSet, ClassNameComputerSet, CimClassComputerSet, CimClassSessionSet
New-CimSessionOption       NoEncryption                     CimCmdlets                       WSManParameterSet
New-CimSessionOption       SkipCACheck                      CimCmdlets                       WSManParameterSet
New-CimSessionOption       SkipCNCheck                      CimCmdlets                       WSManParameterSet
New-CimSessionOption       SkipRevocationCheck              CimCmdlets                       WSManParameterSet
New-CimSessionOption       EncodePortInServicePrincipalName CimCmdlets                       WSManParameterSet
New-CimSessionOption       UseSsl                           CimCmdlets                       WSManParameterSet
New-CimSessionOption       PacketIntegrity                  CimCmdlets                       DcomParameterSet
New-CimSessionOption       PacketPrivacy                    CimCmdlets                       DcomParameterSet
New-Object                 Strict                           Microsoft.PowerShell.Utility     Com
New-WSManInstance          UseSSL                           Microsoft.WSMan.Management       ComputerName
Out-GridView               Wait                             Microsoft.PowerShell.Utility     Wait
Out-GridView               PassThru                         Microsoft.PowerShell.Utility     PassThru
Out-String                 Stream                           Microsoft.PowerShell.Utility     StreamFormatting
Out-String                 NoNewline                        Microsoft.PowerShell.Utility     NoNewLineFormatting
Read-Host                  AsSecureString                   Microsoft.PowerShell.Utility     AsSecureString
Read-Host                  MaskInput                        Microsoft.PowerShell.Utility     AsString
Receive-PSSession          AllowRedirection                 Microsoft.PowerShell.Core        ConnectionUriSessionName, ConnectionUriInstanceId
Receive-PSSession          UseSSL                           Microsoft.PowerShell.Core        ComputerInstanceId, ComputerSessionName
Register-ArgumentCompleter Native                           Microsoft.PowerShell.Core        NativeSet
Remove-Job                 Force                            Microsoft.PowerShell.Core        InstanceIdParameterSet, JobParameterSet, NameParameterSet, SessionIdParameterSet, FilterParameterSet
Remove-WSManInstance       UseSSL                           Microsoft.WSMan.Management       ComputerName
Resolve-Path               Relative                         Microsoft.PowerShell.Management  Path, LiteralPath
Restart-Computer           Wait                             Microsoft.PowerShell.Management  DefaultSet
Select-Object              Wait                             Microsoft.PowerShell.Utility     DefaultParameter, IndexParameter
Select-String              Raw                              Microsoft.PowerShell.Utility     ObjectRaw, FileRaw, LiteralFileRaw
Select-String              Quiet                            Microsoft.PowerShell.Utility     Object, File, LiteralFile
Set-Acl                    ClearCentralAccessPolicy         Microsoft.PowerShell.Security    ByPath, ByLiteralPath
Set-PSDebug                Step                             Microsoft.PowerShell.Core        on
Set-PSDebug                Strict                           Microsoft.PowerShell.Core        on
Set-PSDebug                Off                              Microsoft.PowerShell.Core        off
Set-StrictMode             Off                              Microsoft.PowerShell.Core        Off
Set-TraceSource            Force                            Microsoft.PowerShell.Utility     optionsSet
Set-TraceSource            Debugger                         Microsoft.PowerShell.Utility     optionsSet
Set-TraceSource            PSHost                           Microsoft.PowerShell.Utility     optionsSet
Set-TraceSource            PassThru                         Microsoft.PowerShell.Utility     optionsSet
Set-WSManInstance          UseSSL                           Microsoft.WSMan.Management       ComputerName
Sort-Object                Stable                           Microsoft.PowerShell.Utility     Default
Start-Job                  RunAs32                          Microsoft.PowerShell.Core        FilePathComputerName, ComputerName, LiteralFilePathComputerName
Start-Process              LoadUserProfile                  Microsoft.PowerShell.Management  Default
Start-Process              NoNewWindow                      Microsoft.PowerShell.Management  Default
Start-Process              UseNewEnvironment                Microsoft.PowerShell.Management  Default
Tee-Object                 Append                           Microsoft.PowerShell.Utility     File
Test-WSMan                 UseSSL                           Microsoft.WSMan.Management       ComputerName
Update-TypeData            Force                            Microsoft.PowerShell.Utility     DynamicTypeSet, TypeDataSet
help                       Detailed                                                          DetailedView
help                       Full                                                              AllUsersView
help                       Examples                                                          Examples
help                       Online                                                            Online
help                       ShowWindow                                                        ShowWindow

Code to generate list:

# In a fresh session (-NoProfile, -NonInteractive):
# Ensure modules owned by PowerShell/PowerShell are loaded, otherwise
# the CommandInfo's ParameterSets is empty when getting the command.
$pwshModules = @(
    'CimCmdlets'
    'Microsoft.PowerShell.Core'
    'Microsoft.PowerShell.Diagnostics'
    'Microsoft.PowerShell.Host'
    'Microsoft.PowerShell.Management'
    'Microsoft.PowerShell.Security'
    'Microsoft.PowerShell.Utility'
    'Microsoft.WSMan.Management'
    'PSDiagnostics'
)
Import-Module -Name ($pwshModules -ne 'Microsoft.PowerShell.Core')

# Get commands belonging to PowerShell/PowerShell, including built-in functions (help, oss, etc).
$pwshCmds = @(
    Get-Command -CommandType Cmdlet, Function, Filter -Module $pwshModules
    Get-Command -CommandType Function, Filter | Where-Object -Not Source
) 

# Commands already fixed in #25242.
$alreadyFixed = @(
    'Get-Uptime'
    'New-Guid'
    'Get-Random'
    'Get-SecureRandom'
    'Get-TimeZone'
    'New-PSSession'
    'Split-Path'
    'Test-Connection'
    'Where-Object'
)

foreach ($cmd in $pwshCmds | Where-Object Name -NotIn $alreadyFixed) {
    foreach ($param in $cmd.Parameters.Values) {
        # Only output switch parameters that are in an explicit parameter set.
        if (!$param.SwitchParameter -or $param.ParameterSets.ContainsKey('__AllParameterSets')) { 
            continue 
        }

        [pscustomobject] @{
            Command        = $cmd
            Parameter      = $param.Name
            Source         = $cmd.Source
            InParameterSet = $param.ParameterSets.Keys
        }
    }
}

However, it doesn't cover causes of the issue that don't involve parameter sets at all (e.g., MyInvocation.BoundParameters.ContainsKey('SwitchParam')). So for completeness, there's a total of 450+ parameters that require checking.

Fully automating that will be difficult, I think. Some degree of manual checking (either by searching the code base or testing commands manually) will probably be needed, but naturally it would require substantial effort.

here's a total of 450+ parameters that require checking.

Too much to fix in a reasonable time. Rather, we should ask - are there any cmdlets where there are very annoying problems with switches?

If we don't know any of them now, then I suggest closing this issue. Users can always open a new one if the need arises.

I don't necessarily know about annoying, but I did take a cursory look through the list and the following are broken in a similar way to the ones we've already fixed:

ConvertTo-Csv -UseCulture:$false (results in no delimiter at all)
Export-Csv -UseCulture:$false (results in space as the delimiter)
ConvertFrom-Csv -UseCulture:$false (doesn't parse using default delimiter)
Import-Csv -UseCulture:$false (doesn't parse using default delimiter)
Get-Culture -ListAvailable:$false (behaves like -ListAvailable)
Get-Location -Stack:$false (behaves like -Stack)
Format-Hex -Raw:$false (behaves like -Raw and still emits warning)

It really depends how far we want to take this.

If -Switch:$false should behave as if -Switch wasn't specified, all commands with switches tied to a distinct parameter set are technically broken. E.g.,

Measure-Object, Measure-Object -Line and Measure-Object -Line:$false all behave differently (that is, -Line:$false doesn't behave like omitting the switch or including -Line). Measure-Object has many switches like this split across different sets.
New-Object -TypeName int -Strict:$false should behave like New-Object -TypeName int, but fails because -TypeName/-Strict are in different sets.
All of help's switches.

It's probably not feasible/worth it to fix all of the commands like that.

I suggest ConvertTo-Csv, Export-Csv, ConvertFrom-Csv, Import-Csv, Get-Culture and Get-Location at the very least should be fixed before closing this issue. I've updated the OP accordingly and filed #26513 as a start.

Fix Get-Culture -ListAvailable:$false and Get-Location -Stack:$false

Submitted #27034 — fixes Get-Culture -ListAvailable:$false and Get-Location -Stack:$false. Same if-guard pattern as the 9 previously merged sibling PRs.

Fix Get-Culture -ListAvailable:$false and Get-Location -Stack:$false

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Fix individual commands that do not respect an explicit `$false` value passed to a switch parameter #25242

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Fix individual commands that do not respect an explicit $false value passed to a switch parameter #25242

Description

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Context:

List of commands to fix:

Request

Expected behavior

Actual behavior

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surfingoldelephant commented on Mar 26, 2025

kilasuit commented on Mar 26, 2025

surfingoldelephant commented on Mar 26, 2025

SteveL-MSFT commented on Oct 1, 2025

surfingoldelephant commented on Nov 17, 2025

iSazonov commented on Nov 21, 2025

surfingoldelephant commented on Nov 21, 2025

iSazonov commented on Nov 22, 2025

surfingoldelephant commented on Nov 22, 2025

SufficientDaikon commented on Mar 15, 2026

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Fix individual commands that do not respect an explicit `$false` value passed to a switch parameter #25242