%programfiles% is not expanding in wix registry search - wix

Question

I am using wix registry search in order to locate a plugin directory for a program I am trying to integrate with. The value of the registry key looks like this:
%PROGRAMFILES%\Product\Plugins
When I do a registry search with type="raw" like this:
<Property Id="PLUGINDIR_STRING">
<RegistrySearch Id="PluginDirSearchString"
Root="HKLM"
Key="$(var.PluginDirRegKey)"
Name="$(var.PluginDirRegKeyName)"
Type="raw"
Win64="yes" />
</Property>
I will get the exact string.
When I use type Directory like this:
<Property Id="PLUGINDIR">
<RegistrySearch Id="PluginDirSearch"
Root="HKLM"
Key="$(var.PluginDirRegKey)"
Name="$(var.PluginDirRegKeyName)"
Type="directory"
Win64="yes" />
</Property>
I will get an empty string. I am checking the values like this:
<Condition Message='plugin dir "[PLUGINDIR_STRING]" found using registry key "$(var.PluginDirRegKey)" is not a valid path, make sure the path exist'>PLUGINDIR_STRING AND NOT PLUGINDIR</Condition>
<Condition Message='Unable to find registry key "$(var.PluginDirRegKey)", make sure $(var.PRODUCT) is installed'>PLUGINDIR_STRING</Condition>
The first message is displayed indicating that PLUGINDIR_STRING is found, but not PLUGINDIR. I thought the Directory option should expand %programfiles%? How to correctly handle a registry value like this?
%PROGRAMFILES%\Product\Plugins

Answer 1

The raw search does not work the same as directory search. A raw search returns the values in the registry item. A directory search retrieves the value then checks to see if that registry exists - it literally is a directory search for the directory in that registry item and if it doesn't exist then it will not set the property value. The idea is that if you want to use that directory as an install location it tells you that it doesn't exist.
Anyway a verbose log should verify if this is going on - look at the AppSearch and you may find something like a 1314 error saying that the directory in that registry item does not exist.
I cannot reproduce the error you are seeing. Both raw and directory registry searches are expanding %programfiles% correctly. Everything else you are doing seems correct, so the most likely issue with your failing directory search is that your setup is a 32-bit setup and you are attempting to locate a 64-bit directory. Your AppSearch in a 32-bit install will locate the %programfiles% string in your registry entry, but it will invoke WIN64DUALFOLDERS, and search for the directory in the ProgramFiles(x86) folder. If the directory isn't there you will see an empty property value returned.

Answer 2

Use the well defined MSI property to get the program files location.
You can find the list of well defined properties here
So set your property to [ProgramFilesFolder]\Product\Plugins. There is also ProgramFiles64Folder but from the snippets you supplied I can't tell which one you should be using. Ideally you use a 32-bit installer to install into Program Files on a 32-bit OS and Program Files (x86) on a 64-bit OS and you would use a 64-bit installer to install into Program File on a 64-bit OS.