How to fix “Content not allowed in prolog” Micro service Configuration Exception

Question

Deployer service starts but quickly stops.

On checking the microservice logs in C:\SDL\Web\log\, we found an exception in C:\SDL\Web\log\deployer-combined\cd_core

Caused by: com.tridion.configuration.ConfigurationException: org.xml.sax.SAXParseException; systemId: file:///C:/SDL/Web/deployer-combined/deployer-conf.xml; lineNumber: 1; columnNumber: 1; Content is not allowed in prolog. at com.tridion.configuration.XMLConfigurationReader.readConfiguration( XMLConfigurationReader.java:128) at com.sdl.delivery.deployer.configuration.DeployerConfigurationLoader.configure( DeployerConfigurationLoader.java:134)

Answer 1

Tridion XML configuration files are often manually edited. If you do this, you must always use a TEXT Only editor otherwise your file may get saved with a BOM.

https://en.wikipedia.org/wiki/Byte_order_mark

The Byte Order Mark (BOM) is not handled by Java Xerces XML Parser.

So you get a Configuration Exception “Content is not allowed in prolog”

I recommend that you always script changes to the Tridion configuration files or always use a text only editor.

PowerShell example to save configuration files without a Byte Order Mark.

#
# RemoveBOM.ps1
#

# Byte Order Mark is not handled by Java Xerces XML Parser

# Typical Exception:
# Caused by: com.tridion.configuration.ConfigurationException:
# org.xml.sax.SAXParseException; 
# systemId: file:///C:/SDL/Web/deployer-combined/deployer-conf.xml; 
# lineNumber: 1; columnNumber: 1; Content is not allowed in prolog.

    $Utf8NoBomEncoding = New-Object System.Text.UTF8Encoding($False)   
    $filepath = "C:\sdl\web\deployer-combined\config\deployer-conf.xml"
    $content = Get-Content -Path $filepath
    [System.IO.File]::WriteAllLines($filepath , $content, $Utf8NoBomEncoding)

Also read Dominic's excellent Blog on the BOM
http://dominic.cronin.nl/weblog/deployer-conf-xml-barfs-on-the-bom