I am trying to retrieve the ARPINSTALLLOCATION during the installation of a Major Upgrade version of the software.

Following this info I managed to set the ARPINSTALLLOCATION to the custom path.

However, retrieving it again isn't working. I've tried many things over the past days but it keeps defaulting back to the default installation path instead of the custom one.

<InstallUISequence>
  <AppSearch After="FindRelatedProducts"/>
  ...
</InstallUISequence>

<Property Id="WIXUI_INSTALLDIR" Value="APPROOTDIRECTORY">
  <RegistrySearch Id="FindInstallLocation"
      Root="HKLM"
      Key="Software\Microsoft\Windows\CurrentVersion\Uninstall\[OLDERVERSIONBEINGUPGRADED]"
      Name="InstallLocation"
      Type="raw" />
</Property>

In the custom WixUI_InstallDir UI I have this in the CustomInstallDirDlg

<Control Id="Folder" Type="PathEdit" X="20" Y="90" Width="260" Height="18" Property="WIXUI_INSTALLDIR" Indirect="yes" />

The alternative install path is in the registry, but it isn't retrieved and shown in the control. What am I doing wrong here?

-Birkoff