Unresolved reference to the "WixComponentGroup: MyWebWebComponents" symbol in the section

Question

I followed the code below, which is the product.wxs file. But I ran into an error as shown below:

Error 5 Unresolved reference to the symbol "WixComponentGroup: MyWebWebComponents" in the section "Product: {} '

<?xml version="1.0" encoding="UTF-8"?> <Wix xmlns="http://schemas.microsoft.com/wix/2006/wi" xmlns:util="http://schemas.microsoft.com/wix/UtilExtension" xmlns:iis="http://schemas.microsoft.com/wix/IIsExtension"> <Product Id="702881b5-9a64-4ab8-ab47-f3babcd950a2" Name="WixApplication" Language="1033" Version="1.0.0.0" Manufacturer="HexWireless" UpgradeCode="42b7872b-78c8-4a0b-abcd-28a30c9804ab"> <Package InstallerVersion="200" Compressed="yes" Platform="x64" InstallScope="perMachine"/> <!--<Media Id="1" Cabinet="media1.cab" EmbedCab="yes" />--> <!--Find the Path to the sqlcmd.exe by performing a registry search. This is hardcoded for SQL 2012. Change 110 to 100 for 2008. Might need to change the script too.--> <Property Id="SQLBINDIR"> <RegistrySearch Id="SqlBinDir" Root="HKLM" Key="SOFTWARE\Microsoft\Microsoft SQL Server\110\Tools\ClientSetup" Name="Path" Type="raw" Win64="yes"/> </Property> <Condition Message="Microsoft SQL Server 2012 needs to be installed before this installer can run"> <![CDATA[SQLBINDIR]]> </Condition> <Directory Id="TARGETDIR" Name="SourceDir"> <Directory Id="INSTALLLOCATION" Name="Database"> <Component Id="Database" Guid="a8dc2Fcd-087d-e393-b059-c67877e51b8a"> <File Id="DatabaseScript" Source="SQLScripts\HexWireless.sql"/> <RemoveFile Id ="RemoveInstall.log" Name="Install.log" On="uninstall" /> </Component> </Directory> <Directory Id="INSTALLDIR" Name="PFiles"> <Directory Id="WixService" Name="Service"> <Component Id="WixWindowsServiceComponent" DiskId="1" Guid="6f51c0f3-776c-4aec-a200-1f199352c6c3" Win64="yes"> <File Id="WixService.exe" Name="WixService.exe" Source="$(var.WixService.TargetDir)\WixService.exe"/> <ServiceInstall Id="InstallWixService" DisplayName="WixService" Name="WixService.exe" Description="WixService" Account="NT Authority\Network Service" ErrorControl="normal" Start="demand" Type="ownProcess" Vital="yes" /> <ServiceControl Id="ControlWixService" Name="WixService.exe" Stop="uninstall" Remove="uninstall" /> </Component> </Directory> </Directory> <Directory Id="INSTALLFOLDER" Name="Publish"> </Directory> </Directory> <Feature Id="ProductFeature" Title="WebApplication" Level="1"> <Feature Id="Database" Title="Database" Description="DatabaseScript" Level="1" Display="expand" AllowAdvertise="no" ConfigurableDirectory="INSTALLLOCATION" Absent="allow"> <Feature Id="WixWindowsServiceComponent" Title="Service" Description="WixService" Level="1" Display="expand" AllowAdvertise="no" ConfigurableDirectory="INSTALLDIR" Absent="allow"> <ComponentGroupRef Id="WixWebsiteIssConfiguration" /> <ComponentRef Id="Database"/> <ComponentRef Id="WixWindowsServiceComponent"/> <ComponentGroupRef Id="MyWebWebComponents"/> </Feature> </Feature> </Feature> <Property Id="INSTALLDIR" Value="D:" /> <Media Id="1" Cabinet="WixWindowsServiceComponent.cab" EmbedCab="yes" /> <InstallExecuteSequence> <!--If the database feature is selected these actions will run to install the DB--> <Custom Action="Database.cmd" After="InstallFiles" > <![CDATA[NOT Installed]]> </Custom> <!--Ensure this runs after the custom action to set up the properties for its cmd line--> <Custom Action="Database" After="Database.cmd"> <![CDATA[NOT Installed]]> </Custom> </InstallExecuteSequence> <UI> <UIRef Id="GUI"/> <UIRef Id="WixUI_ErrorProgressText" /> </UI> <!--This is the sequence script. Best way to understand this is by running sqlcmd -? Use "property" Custom action to get variable substitution working--> <CustomAction Id="Database.cmd" Property="Database" Value="&quot;[SQLBINDIR]sqlcmd.exe&quot; -E -S &quot;[SQLSERVER]&quot; -i &quot;[#DatabaseScript]&quot; -o &quot;[INSTALLLOCATION]HexWireless.log&quot;"/> <!-- Note that the cmd line and args will come from a property with the same name as the custom action, this has been set by the custom action above --> <CustomAction Id="Database" BinaryKey="WixCA" DllEntry="CAQuietExec" Return="check" Execute="deferred" Impersonate="yes" /> </Product> </Wix> 

Thanks in advance.