diff --git a/test/powershell/engine/ExperimentalFeature/EnableDisable-ExperimentalFeature.Tests.ps1 b/test/powershell/engine/ExperimentalFeature/EnableDisable-ExperimentalFeature.Tests.ps1
index d26bc41dd5..1a11a668fd 100644
--- a/test/powershell/engine/ExperimentalFeature/EnableDisable-ExperimentalFeature.Tests.ps1
+++ b/test/powershell/engine/ExperimentalFeature/EnableDisable-ExperimentalFeature.Tests.ps1
@@ -10,11 +10,26 @@ Describe "Enable-ExperimentalFeature and Disable-ExperimentalFeature tests" -tag
         $systemConfigPath = (Get-PowerShellConfiguration -Scope AllUsers).Path
         $userConfigPath = (Get-PowerShellConfiguration -Scope CurrentUser).Path
 
+        # The legacy $PSHOME config may exist (e.g., preview builds).
+        # Back it up so tests start clean. Also track it separately because
+        # writes go to the new platform location, not the legacy path.
+        $legacyConfigPath = Join-Path $PSHOME "powershell.config.json"
+        $legacyConfigExists = $false
+        if (($legacyConfigPath -ne $systemConfigPath) -and (Test-Path $legacyConfigPath)) {
+            $legacyConfigExists = $true
+            Move-Item $legacyConfigPath "$legacyConfigPath.backup" -Force -ErrorAction SilentlyContinue
+        }
+
         $systemConfigDir = Split-Path $systemConfigPath
         if (!(Test-Path $systemConfigDir)) {
             $null = New-Item -ItemType Directory -Path $systemConfigDir -Force -ErrorAction SilentlyContinue
         }
 
+        $userConfigDir = Split-Path $userConfigPath
+        if (!(Test-Path $userConfigDir)) {
+            $null = New-Item -ItemType Directory -Path $userConfigDir -Force -ErrorAction SilentlyContinue
+        }
+
         $systemConfigExists = $false
         if (Test-Path $systemConfigPath) {
             $systemConfigExists = $true
@@ -33,6 +48,10 @@ Describe "Enable-ExperimentalFeature and Disable-ExperimentalFeature tests" -tag
     }
 
     AfterAll {
+        if ($legacyConfigExists) {
+            Move-Item "$legacyConfigPath.backup" $legacyConfigPath -Force -ErrorAction SilentlyContinue
+        }
+
         if ($systemConfigExists) {
             Move-Item "$systemConfigPath.backup" $systemConfigPath -Force -ErrorAction SilentlyContinue
         }
@@ -47,6 +66,9 @@ Describe "Enable-ExperimentalFeature and Disable-ExperimentalFeature tests" -tag
     AfterEach {
         Remove-Item $systemConfigPath -Force -ErrorAction SilentlyContinue
         Remove-Item $userConfigPath -Force -ErrorAction SilentlyContinue
+        if ($legacyConfigPath -ne $systemConfigPath) {
+            Remove-Item $legacyConfigPath -Force -ErrorAction SilentlyContinue
+        }
     }
 
     It "Enable-ExperimentalFeature will enable Experimental Feature for scope: <scope>" -TestCases @(
diff --git a/test/powershell/engine/ExperimentalFeature/Get-ExperimentalFeature.Tests.ps1 b/test/powershell/engine/ExperimentalFeature/Get-ExperimentalFeature.Tests.ps1
index 47ad3c8413..dce719c896 100644
--- a/test/powershell/engine/ExperimentalFeature/Get-ExperimentalFeature.Tests.ps1
+++ b/test/powershell/engine/ExperimentalFeature/Get-ExperimentalFeature.Tests.ps1
@@ -10,11 +10,23 @@ Describe "Get-ExperimentalFeature Tests" -tags "Feature","RequireAdminOnWindows"
         $systemConfigPath = (Get-PowerShellConfiguration -Scope AllUsers).Path
         $userConfigPath = (Get-PowerShellConfiguration -Scope CurrentUser).Path
 
+        $legacyConfigPath = Join-Path $PSHOME "powershell.config.json"
+        $legacyConfigExists = $false
+        if (($legacyConfigPath -ne $systemConfigPath) -and (Test-Path $legacyConfigPath)) {
+            $legacyConfigExists = $true
+            Move-Item $legacyConfigPath "$legacyConfigPath.backup" -Force -ErrorAction SilentlyContinue
+        }
+
         $systemConfigDir = Split-Path $systemConfigPath
         if (!(Test-Path $systemConfigDir)) {
             $null = New-Item -ItemType Directory -Path $systemConfigDir -Force -ErrorAction SilentlyContinue
         }
 
+        $userConfigDir = Split-Path $userConfigPath
+        if (!(Test-Path $userConfigDir)) {
+            $null = New-Item -ItemType Directory -Path $userConfigDir -Force -ErrorAction SilentlyContinue
+        }
+
         $systemConfigExists = $false
         if (Test-Path $systemConfigPath) {
             $systemConfigExists = $true
@@ -34,6 +46,10 @@ Describe "Get-ExperimentalFeature Tests" -tags "Feature","RequireAdminOnWindows"
     }
 
     AfterAll {
+        if ($legacyConfigExists) {
+            Move-Item "$legacyConfigPath.backup" $legacyConfigPath -Force -ErrorAction SilentlyContinue
+        }
+
         if ($systemConfigExists -and (Test-CanWriteToSystemConfigDir)) {
             Move-Item "$systemConfigPath.backup" $systemConfigPath -Force -ErrorAction SilentlyContinue
         }
@@ -51,6 +67,9 @@ Describe "Get-ExperimentalFeature Tests" -tags "Feature","RequireAdminOnWindows"
         }
 
         Remove-Item $userConfigPath -Force -ErrorAction SilentlyContinue
+        if ($legacyConfigPath -ne $systemConfigPath) {
+            Remove-Item $legacyConfigPath -Force -ErrorAction SilentlyContinue
+        }
     }
 
     Context "Feature disabled tests" {
diff --git a/test/powershell/engine/PSConfiguration/Get-PowerShellConfiguration.Tests.ps1 b/test/powershell/engine/PSConfiguration/Get-PowerShellConfiguration.Tests.ps1
index 6f7bb5e408..7dcbaa2bb0 100644
--- a/test/powershell/engine/PSConfiguration/Get-PowerShellConfiguration.Tests.ps1
+++ b/test/powershell/engine/PSConfiguration/Get-PowerShellConfiguration.Tests.ps1
@@ -6,8 +6,9 @@ Describe "Get-PowerShellConfiguration Tests" -Tags "CI" {
     It "Returns both scopes when no -Scope is specified" {
         $configs = Get-PowerShellConfiguration
         $configs | Should -HaveCount 2
-        $configs[0].Scope | Should -Be "AllUsers"
-        $configs[1].Scope | Should -Be "CurrentUser"
+        $scopes = $configs.Scope
+        $scopes | Should -Contain "AllUsers"
+        $scopes | Should -Contain "CurrentUser"
     }
 
     It "Returns AllUsers scope when -Scope AllUsers is specified" {
diff --git a/test/tools/Modules/HelpersCommon/HelpersCommon.psm1 b/test/tools/Modules/HelpersCommon/HelpersCommon.psm1
index f90b275bba..034683be2b 100644
--- a/test/tools/Modules/HelpersCommon/HelpersCommon.psm1
+++ b/test/tools/Modules/HelpersCommon/HelpersCommon.psm1
@@ -355,24 +355,30 @@ function Test-CanWriteToSystemConfigDir {
 
     $script:CanWriteToSystemConfigDir = $false
     $dir = Split-Path (Get-PowerShellConfiguration -Scope AllUsers).Path
+    $createdDir = $false
     if (!(Test-Path $dir)) {
         try {
             $null = New-Item -ItemType Directory -Path $dir -Force -ErrorAction Stop
+            $createdDir = $true
             $script:CanWriteToSystemConfigDir = $true
         } catch {
             ; # do nothing
         }
     } else {
         try {
-            $testFile = Join-Path $dir ".pester-write-test"
-            Set-Content -Path $testFile -Value '' -ErrorAction Stop
-            Remove-Item $testFile -Force -ErrorAction SilentlyContinue
+            $testFileName = Join-Path $dir (New-Guid).Guid
+            $null = New-Item -ItemType File -Path $testFileName -ErrorAction Stop
             $script:CanWriteToSystemConfigDir = $true
+            Remove-Item -Path $testFileName -ErrorAction SilentlyContinue
         } catch {
             ; # do nothing
         }
     }
 
+    if ($createdDir) {
+        Remove-Item $dir -Force -ErrorAction SilentlyContinue
+    }
+
     $script:CanWriteToSystemConfigDir
 }