diff --git a/packaging/windows/check-install-policy.ps1 b/packaging/windows/check-install-policy.ps1
index 451295a2e..a4a14bc64 100644
--- a/packaging/windows/check-install-policy.ps1
+++ b/packaging/windows/check-install-policy.ps1
@@ -140,6 +140,28 @@ try {
       $ui['CraftScopeDlg'] -lt $ui['CraftRestoreUserFolder'] -and $ui['CraftRestoreUserFolder'] -lt $ui['CostInitialize'])) {
     throw 'Scope must be chosen after AppSearch and before FindRelatedProducts, launch checks and costing.'
   }
+  # Windows Installer resolves Program Files for the context it started in, before the wizard's scope choice.
+  # The wizard therefore sets the new-install folder itself, and only in the wizard.
+  $defaults = @(Read-Rows $database 'SELECT `Action`, `Sequence`, `Condition` FROM `InstallUISequence`' 3 | Where-Object { $_[0] -like 'CraftDefault*' })
+  if ($defaults.Count -lt 2) { throw 'The wizard must set the new-install folder after the scope page; Program Files is resolved before the choice.' }
+  foreach ($row in $defaults) {
+    if (-not ($ui['CraftScopeDlg'] -lt [int]$row[1] -and [int]$row[1] -lt $ui['CostInitialize'])) { throw "$($row[0]) must run after the scope page and before costing." }
+  }
+  if (@(Read-Rows $database 'SELECT `Action` FROM `InstallExecuteSequence`' 1 | Where-Object { $_[0] -like 'CraftDefault*' }).Count) {
+    throw 'Silent installs must not use the wizard-only default folder actions.'
+  }
+  foreach ($scope in @('1', '')) {
+    Set-SessionProperty $session 'ALLUSERS' $scope
+    Set-SessionProperty $session 'INSTALLFOLDER' ''
+    Set-SessionProperty $session 'CRAFT_MACHINE_DIR' ''
+    Set-SessionProperty $session 'CRAFT_USER_DIR' ''
+    foreach ($row in @($defaults | Sort-Object { [int]$_[1] })) {
+      if ($session.EvaluateCondition($row[2]) -eq 1 -and $session.DoAction($row[0]) -ne 1) { throw "$($row[0]) failed." }
+    }
+    $folder = Get-SessionProperty $session 'INSTALLFOLDER'
+    $wanted = if ($scope -eq '1') { '^[A-Za-z]:\\Program Files( \(x86\))?\\ArtCraft\\[^\\]+\\$' } else { '^' + [regex]::Escape($env:LOCALAPPDATA) + '\\Programs\\ArtCraft\\[^\\]+\\$' }
+    if ($folder -notmatch $wanted) { throw "Wizard default folder for ALLUSERS='$scope' is '$folder'." }
+  }
   $execute = @{}
   foreach ($row in (Read-Rows $database 'SELECT `Action`, `Sequence` FROM `InstallExecuteSequence`' 2)) { $execute[$row[0]] = [int]$row[1] }
   foreach ($action in @('CraftRestoreUserFolder','CraftRestoreMachineFolder')) {
@@ -177,7 +199,7 @@ try {
     $allUsers = Get-SessionProperty $session 'ALLUSERS'
     $perUser = Get-SessionProperty $session 'MSIINSTALLPERUSER'
     if (($choice -eq 'machine' -and ($allUsers -ne '1' -or $perUser)) -or
-        ($choice -eq 'user' -and ($allUsers -ne '2' -or $perUser -ne '1'))) {
+        ($choice -eq 'user' -and ($allUsers -or $perUser -ne '1'))) {
       throw 'Scope selector does not reset the requested installation context.'
     }
   }
diff --git a/packaging/windows/install-policy.wxi b/packaging/windows/install-policy.wxi
index 7ed031649..669c08126 100644
--- a/packaging/windows/install-policy.wxi
+++ b/packaging/windows/install-policy.wxi
@@ -1,6 +1,9 @@
 <?xml version="1.0" encoding="utf-8"?>
 <Include xmlns="http://wixtoolset.org/schemas/v4/wxs">
   <!-- Choose scope before launch checks and directory costing. Never move an existing copy. -->
+  <!-- Only for me leaves ALLUSERS unset. Publishing ALLUSERS=2 here makes FindRelatedProducts treat the run as
+       per-machine and skip the existing per-user copy, so an interactive upgrade installs beside it
+       (two registered products, and uninstall leaves files behind). Checked with real msiexec runs. -->
   <Property Id="INSTALLFOLDER" Secure="yes" />
   <Property Id="CRAFT_SCOPE" Value="user" Secure="yes" />
   <Property Id="CRAFT_U_DIR" Secure="yes"><RegistrySearch Id="CRAFT_U_DIRSearch" Root="HKCU" Key="Software\EffectCraft" Name="InstallDir" Type="raw" /></Property>
@@ -25,6 +28,16 @@
   <Property Id="CRAFT_MACHINE_DIR" Secure="yes" />
   <SetProperty Id="CRAFT_SCOPE" Action="CraftPreferMachineScope" Value="machine" After="CraftMFromLegacyExe" Sequence="ui" Condition="ALLUSERS = 1 OR (CRAFT_MACHINE_DIR AND NOT CRAFT_USER_DIR)" />
   <SetProperty Id="INSTALLFOLDER" Action="CraftRestoreUserFolder" Value="[CRAFT_USER_DIR]" Before="CostInitialize" Sequence="both" Condition="NOT INSTALLFOLDER AND ALLUSERS &lt;&gt; 1 AND CRAFT_USER_DIR" />
+  <!-- The wizard can change the context after Windows Installer has already resolved Program Files for the first one.
+       Give the new-install folder explicitly so Everyone never lands in the profile and Only for me never lands in Program Files. -->
+  <?if $(sys.BUILDARCH) = x86 ?>
+  <SetProperty Id="INSTALLFOLDER" Action="CraftDefaultMachineFolder" Value="[%ProgramFiles(x86)]\ArtCraft\EffectCraft\" After="CraftRestoreUserFolder" Sequence="ui" Condition="NOT INSTALLFOLDER AND ALLUSERS = 1 AND VersionNT64" />
+  <SetProperty Id="INSTALLFOLDER" Action="CraftDefaultMachineFolder32" Value="[%ProgramFiles]\ArtCraft\EffectCraft\" After="CraftDefaultMachineFolder" Sequence="ui" Condition="NOT INSTALLFOLDER AND ALLUSERS = 1 AND NOT VersionNT64" />
+  <SetProperty Id="INSTALLFOLDER" Action="CraftDefaultUserFolder" Value="[LocalAppDataFolder]Programs\ArtCraft\EffectCraft\" After="CraftDefaultMachineFolder32" Sequence="ui" Condition="NOT INSTALLFOLDER AND ALLUSERS &lt;&gt; 1" />
+  <?else?>
+  <SetProperty Id="INSTALLFOLDER" Action="CraftDefaultMachineFolder" Value="[%ProgramW6432]\ArtCraft\EffectCraft\" After="CraftRestoreUserFolder" Sequence="ui" Condition="NOT INSTALLFOLDER AND ALLUSERS = 1" />
+  <SetProperty Id="INSTALLFOLDER" Action="CraftDefaultUserFolder" Value="[LocalAppDataFolder]Programs\ArtCraft\EffectCraft\" After="CraftDefaultMachineFolder" Sequence="ui" Condition="NOT INSTALLFOLDER AND ALLUSERS &lt;&gt; 1" />
+  <?endif?>
   <SetProperty Id="INSTALLFOLDER" Action="CraftRestoreMachineFolder" Value="[CRAFT_MACHINE_DIR]" Before="CraftRestoreUserFolder" Sequence="both" Condition="NOT INSTALLFOLDER AND ALLUSERS = 1 AND CRAFT_MACHINE_DIR" />
   <Launch Condition="Installed OR ALLUSERS &lt;&gt; 1 OR NOT CRAFT_USER_DIR" Message="This app is already installed for your account. Choose Only for me to update it, or uninstall that copy before changing who it is installed for." />
   <Launch Condition="Installed OR ALLUSERS = 1 OR NOT CRAFT_MACHINE_DIR" Message="This app is already installed for everyone. Choose Everyone to update it, or pass ALLUSERS=1 to msiexec. Uninstall that copy before changing who it is installed for." />
@@ -42,7 +55,7 @@
       </Control>
       <Control Id="Next" Type="PushButton" X="214" Y="182" Width="66" Height="20" Default="yes" Text="Next">
         <Publish Property="ALLUSERS" Value="1" Order="1" Condition="CRAFT_SCOPE = &quot;machine&quot;" />
-        <Publish Property="ALLUSERS" Value="2" Order="2" Condition="CRAFT_SCOPE = &quot;user&quot;" />
+        <Publish Property="ALLUSERS" Value="{}" Order="2" Condition="CRAFT_SCOPE = &quot;user&quot;" />
         <Publish Property="MSIINSTALLPERUSER" Value="{}" Order="3" Condition="CRAFT_SCOPE = &quot;machine&quot;" />
         <Publish Property="MSIINSTALLPERUSER" Value="1" Order="4" Condition="CRAFT_SCOPE = &quot;user&quot;" />
         <Publish Event="EndDialog" Value="Return" Order="5" />