How to modify the component .xml file with utils:XmlFile using WIX? - wix

Question

I am trying to create an installer which also installs the xml-file depending on input values, entered in separate dialog. Here
</Component>
<Component Id="ConfigXMLDocument">
<File Id ="Config" KeyPath="yes" DiskId="1" Vital ="yes" Source="$(var.Server.ProjectDir)config.xml"/>
<CreateFolder Directory="INSTALLFOLDER">
<util:PermissionEx User="Users" ChangePermission="yes" GenericAll="yes"/>
</CreateFolder>
<util:XmlFile ElementPath ="root/Server/servername" File ="[INSTALLFORDER]config.xml" Sequence="1" Id ="SERVERNAME"
Action ="setValue" Value ="THIS VALUE IS NOT BEING SET" SelectionLanguage="XPath"/>
<util:XmlFile ElementPath ="root/Server/listenport" File ="[INSTALLFORDER]config.xml" Sequence="2" Id ="PORT"
Action ="setValue" Value ="THIS ONE EITHER"/>
</Component>
The problem is that there are no errors and all the paths are resolved correctly, but the installed file remains the same as original.
If I try to change any other XML-file, It works, but not the one installed.
I found simmilar issues online, but no answers fixed mine.
Is it possible that XmlFile is just changing file before file is installed? And what else can cause such problem?

Answer 1

It appeared to be not one, but two issues.
The first one was to use FIle ID instead of path, so I replaced this
File ="[INSTALLFORDER]config.xml"
with this:
File ="[#Config]"
But It still didn`t work, during the installation appeared an error that the installer cannot find the file config.xml, so i changed the InstallExecuteSequence to this:
<InstallExecuteSequence>
<Custom Action="SchedXmlFile" After="InstallFiles" />
</InstallExecuteSequence>
UPD. This still did not work fine. WIX could not open the file with error:
Failed to open XML file path/config.xml, system error: -2147024786
The error appeared to be that wix cannot recognize the BOM in the XML file for some reason:
<?xml version"1.0" encoding="UTF-8" ?>
So i just removed it.
Hope this helps.