condition - WIX Directory Search Always Fails -

it seems no matter do, condition put in product in wix blocks install running. below i've put simple code should check if program file directory exists , if does, run installer. message saying "program files folder not found." indicating condition returns false. missing here?

<?xml version="1.0" encoding="utf-8"?> <wix xmlns="http://schemas.microsoft.com/wix/2006/wi"> <product id="*" name="setupproject1" language="1033" version="1.0.0.0" manufacturer="toshiba" upgradecode="bb557911-769b-4a30-8461-3ad860ddc10e">     <package installerversion="200" compressed="yes" installscope="permachine" />      <majorupgrade downgradeerrormessage="a newer version of [productname] installed." />     <mediatemplate />  <property id="pffolder" >   <directorysearch id="systemfolderdriverversion" path="[programfilesfolder]">   </directorysearch> </property>  <condition message="program files folder not found.">   <![cdata[pffolder]]> </condition>       <feature id="productfeature" title="setupproject1" level="1">         <componentgroupref id="productcomponents" />     </feature> </product>  <fragment>     <directory id="targetdir" name="sourcedir">         <directory id="programfilesfolder">             <directory id="installfolder" name="setupproject1" />         </directory>     </directory> </fragment>  <fragment>     <componentgroup id="productcomponents" directory="installfolder">         <!-- todo: remove comments around component element , componentref below in order add resources installer. -->         <!-- <component id="productcomponent"> -->             <!-- todo: insert files, registry keys, , other resources here. -->         <!-- </component> -->     </componentgroup> </fragment> 

add assigntoproperty="yes" directorysearch element. don't think need wrap property name in cdata block.