XML Error
– Task applicationcontent has failed with an unknown exception
![](http://get-spnote.com/wp-content/uploads/2023/04/task-app.png)
SharePoint 2013 Product Configuration wizard Failed during the Cumulative Update installation with below error
Task applicationcontent has failed with an unknown exception
ERR Exception: System.NullReferenceException: Object reference not set to an instance of an object.
at Microsoft.SharePoint.Administration.SPAspConfigurationFile.ApplyActionToXmlDocument(XmlDocument xdAction, XmlDocument xd, String sourceFileName, SupportedXmlDocutmentActions supportedActions)
at Microsoft.SharePoint.Administration.SPAspConfigurationFile.MergeWebConfig(XmlDocument xdWebConfig, String fileMask)
at Microsoft.SharePoint.Administration.SPWebService.ApplyApplicationContentToLocalServer()
at Microsoft.SharePoint.PostSetupConfiguration.ApplicationContentTask.Run()
at Microsoft.SharePoint.PostSetupConfiguration.TaskThread.ExecuteTask(
Finally Microsoft Article came in to rescue saying this error caused because Web Application Web Configs are having Commented lines <!—comments –!>
When we remove the comments in Web Config PSConfig executed successfully
Microsoft Article