PowerShell · daxian-dbw · Aug 4, 2025 · Jul 9, 2024 · Jul 29, 2025 · Jul 29, 2025
@@ -1923,9 +1923,7 @@ internal Pipeline CreatePipeline(RemoteRunspace remoteRunspace)
             // the array-form using values if all UsingExpressions are in the same scope, otherwise, we handle the UsingExpression as
             // if the remote end is PSv2.
             string serverPsVersion = GetRemoteServerPsVersion(remoteRunspace);
-            System.Management.Automation.PowerShell powershellToUse = (serverPsVersion == PSv2)
-                                                                          ? GetPowerShellForPSv2()
-                                                                          : GetPowerShellForPSv3OrLater(serverPsVersion);
+            System.Management.Automation.PowerShell powershellToUse = GetPowerShellForPSv3OrLater(serverPsVersion);
             Pipeline pipeline =
                 remoteRunspace.CreatePipeline(powershellToUse.Commands.Commands[0].CommandText, true);
 
@@ -1946,9 +1944,9 @@ internal Pipeline CreatePipeline(RemoteRunspace remoteRunspace)
         /// </summary>
         private static string GetRemoteServerPsVersion(RemoteRunspace remoteRunspace)
         {
-            if (remoteRunspace.ConnectionInfo is NewProcessConnectionInfo)
+            if (remoteRunspace.ConnectionInfo is not WSManConnectionInfo)
             {
-                // This is for Start-Job. The remote end is actually a child local powershell process, so it must be PSv5 or later
+                // All transport types except for WSManConnectionInfo work with 5.1 or later.
                 return PSv5OrLater;
             }
 
@@ -1957,35 +1955,19 @@ private static string GetRemoteServerPsVersion(RemoteRunspace remoteRunspace)
             {
                 // The remote runspace is not opened yet, or it's disconnected before the private data is retrieved.
                 // In this case we cannot validate if the remote server is running PSv5 or later, so for safety purpose,
-                // we will handle the $using expressions as if the remote server is PSv2.
-                return PSv2;
+                // we will handle the $using expressions as if the remote server is PSv3Orv4.
+                return PSv3Orv4;
             }
 
-            // Unfortunately, the PSVersion value in the private data from PSv3 and PSv4 server is always 2.0.
-            // This got fixed in PSv5, so a PSv5 server will return 5.0. That means we need other way to tell
-            // if the remote server is PSv2 or PSv3+. After PSv3, remote runspace supports connect/disconnect,
-            // so we can use it to differentiate PSv2 from PSv3+.
-            if (remoteRunspace.CanDisconnect)
-            {
-                Version serverPsVersion = null;
-                PSPrimitiveDictionary.TryPathGet(
-                    psApplicationPrivateData,
-                    out serverPsVersion,
-                    PSVersionInfo.PSVersionTableName,
-                    PSVersionInfo.PSVersionName);
-
-                if (serverPsVersion != null)
-                {
-                    return serverPsVersion.Major >= 5 ? PSv5OrLater : PSv3Orv4;
-                }
-
-                // The private data is available but we failed to get the server powershell version.
-                // This should never happen, but in case it happens, handle the $using expressions
-                // as if the remote server is PSv2.
-                Dbg.Assert(false, "Application private data is available but we failed to get the server powershell version. This should never happen.");
-            }
+            PSPrimitiveDictionary.TryPathGet(
+                psApplicationPrivateData,
+                out Version serverPsVersion,
+                PSVersionInfo.PSVersionTableName,
+                PSVersionInfo.PSVersionName);
 
-            return PSv2;
+            // PSv5 server will return 5.0 whereas older versions will always be 2.0. As we don't care about v2
+            // anymore we can use a simple ternary check here to differenciate v5 using behaviour vs v3/4.
+            return serverPsVersion != null && serverPsVersion.Major >= 5 ? PSv5OrLater : PSv3Orv4;
         }
 
         /// <summary>
@@ -2059,7 +2041,6 @@ private void WriteErrorCreateRemoteRunspaceFailed(Exception e, Uri uri)
         /// </summary>
         private const string PSv5OrLater = "PSv5OrLater";
         private const string PSv3Orv4 = "PSv3Orv4";
-        private const string PSv2 = "PSv2";
 
         private System.Management.Automation.PowerShell _powershellV2;
         private System.Management.Automation.PowerShell _powershellV3;

@@ -27,14 +27,14 @@ function Start-PwshProcess
 
 Describe 'NamedPipe Custom Remote Connection Tests' -Tags 'Feature','RequireAdminOnWindows' {
 
-    BeforeAll {
+    BeforeEach {
         Import-Module -Name Microsoft.PowerShell.NamedPipeConnection -ErrorAction Stop
 
         $script:PwshProcId = Start-PwshProcess
         $script:session = $null
     }
 
-    AfterAll {
+    AfterEach {
         if ($null -ne $script:session)
         {
             Remove-PSSession -Session $script:session
@@ -57,6 +57,10 @@ Describe 'NamedPipe Custom Remote Connection Tests' -Tags 'Feature','RequireAdmi
     # Skip this timeout test for non-Windows platforms, because dotNet named pipes do not honor the 'NumberOfServerInstances'
     # property and allows connection to a currently connected server.
     It 'Verifies timeout error when trying to connect to pwsh process with current connection' -Skip:(!$IsWindows) {
+        # We start an active connection to have it block the second connection attempt.
+        $script:session = New-NamedPipeSession -ProcessId $script:PwshProcId -ConnectingTimeout 10 -Name CustomNPConnection -ErrorAction Stop
+
+        # The above connection means the named pipe server is busy and won't allow this second connection.
         $brokenSession = New-NamedPipeSession -ProcessId $script:PwshProcId -ConnectingTimeout 2 -Name CustomNPConnection -ErrorAction Stop
 
         # Verify expected broken session
@@ -66,4 +70,29 @@ Describe 'NamedPipe Custom Remote Connection Tests' -Tags 'Feature','RequireAdmi
 
         $brokenSession | Remove-PSSession
     }
+
+    It 'Passes $using: with PSv5 compatibility in Invoke-Command' {
+        $script:session = New-NamedPipeSession -ProcessId $script:PwshProcId -ConnectingTimeout 10 -Name CustomNPConnection -ErrorAction Stop
+
+        Function Test-Function {
+            'foo'
+        }
+
+        # The v2 engine will choke on a var with '-' in the name and the v3/v4
+        # using logic will revert to the v2 branch if $using is in a new scope.
+        # By using a function and a new scope we can verify the v5 logic is
+        # used and not the v2-4 one.
+        $result = Invoke-Command -Session $script:session -ScriptBlock {
+            ${function:Test-Function} = ${using:function:Test-Function}
+
+            Test-Function
+
+            # Running in a new scope triggers the v2 logic if the v3/v4 branch
+            # was used.
+            & { (${using:function:Test-Function}).Trim() }
+        }
+        $result.Count | Should -Be 2
+        $result[0] | Should -BeExactly foo
+        $result[1] | Should -BeExactly "'foo'"
+    }
 }
@@ -551,7 +551,8 @@ function Get-HelpNetworkTestCases
 
     # Command discovery does not follow symlinks to network locations for module qualified paths
     $networkBlockedError = "CommandNameNotAllowed,Microsoft.PowerShell.Commands.GetHelpCommand"
-    $scriptBlockedError = "ScriptsNotAllowed"
+    # This error may change as long as no test cases start failing for other reasons
+    $scriptBlockedError = "CommandNotFoundException"
 
     $formats = @(
         '//{0}/share/{1}'