Wix SubDirectories in ComponentGroups - wix

Question

I want to predefine Subfolders for my ComponentGroups.
<?xml version="1.0" encoding="UTF-8"?>
<Wix xmlns="http://schemas.microsoft.com/wix/2006/wi">
<?include Constants.wxi?>
<Fragment>
<ComponentGroup Id="CG.MYLIBRARY" Directory="INSTALLFOLDER">
<Component Id="C.MYLIBRARY" Guid="*">
<File Id="MYLIBRARY" Source="$(var.MyProject.TargetPath)" KeyPath="yes" Checksum="yes" />
</Component>
<ComponentGroupRef Id="CG.DependencyLibrary" />
<!-- Resources -->
<Component Directory="Configuration">
<File Id="MyFile" Source="$(var.MyProject.TargetPath)\Configuration\MyFile" />
</Component>
</ComponentGroup>
</Fragment>
</Wix>
So I want MyLibrary.dll at my TopDirectory - where ever is "INSTALLFOLDER",
but I want automaticly MyFile.xml in a Subdirectory named Configuration.
#InstallFolder
-> MyLibrary.dll
-> DependencyLibrary.dll
#InstallFolder\Configuration
--> MyFile.xml
But when I try it like that - i just get:
The Component/#Directory attribute cannot be specified when the
Component element is nested underneath a Directory element. If this
Component is a member of a ComponentGroup where
ComponentGroup/#Directory is set, then the Component/#Directory
attribute should be removed.
Why do I have to remove the Directory-Element, when i just want subfolders under the given Directory in my ComponentGroup?

Answer 1

I don't use this construct (ComponentGroup), but this compiles:
<...>
<Fragment>
<Directory Id="TARGETDIR" Name="SourceDir">
<Directory Id="ProgramFilesFolder">
<Directory Id="INSTALLFOLDER" Name="SetupProject4">
<Directory Id="Configuration" />
</Directory>
</Directory>
</Directory>
</Fragment>
<...>
<Fragment>
<ComponentGroup Id="ProductComponents">
<Component Id="C.MYLIBRARY" Directory="INSTALLFOLDER">
<File Source="1.txt" />
</Component>
<Component Directory="Configuration">
<File Source="2.txt" />
</Component>
</ComponentGroup>
</Fragment>