title: Implementing logging in SharePoint 2010 using the SharePoint Guidance library
body: <p>I tried to use the SharePoint Guidance library and i got this error.
  Someone has a answer or propositions?</p>
  
  <p>Thanks</p>
  
  <pre><code>Error is :
  One or more error occurred while writing messages into the log.\r\nThe error while writing to the EventLog was:An exception has occurred.
      ExceptionType: 'LoggingException'
      ExceptionMessage: 'The Category 'Custom Error/DUET' was not found in the diagnostic categories collections.'
      StackTrace: '   at Microsoft.Practices.SharePoint.Common.Logging.DiagnosticsService.GetCategory(String categoryName)
             at Microsoft.Practices.SharePoint.Common.Logging.DiagnosticsService.LogTrace(String message, Int32 eventId, TraceSeverity severity, String categoryName)
             at Microsoft.Practices.SharePoint.Common.Logging.TraceLogger.Trace(String message, Int32 eventId, TraceSeverity severity, String category)
             at Microsoft.Practices.SharePoint.Common.Logging.SharePointLogger.WriteToDeveloperTrace(String message, Int32 eventId, TraceSeverity severity, String category)'
      Source: 'Microsoft.Practices.SharePoint.Common'
      TargetSite: 'Microsoft.SharePoint.Administration.SPDiagnosticsCategory GetCategory(System.String)'
  \r\n Orginal logged message was: An error occurred while writing tot the Trace Log, trace message:kaka Error in Constant recovery
      ExceptionType: 'Exception'
      ExceptionMessage: 'testing sohail'
      StackTrace: ''
      Source: ''
      TargetSite: ''
  </code></pre>