Recently Fiddler has taken to flooding OutputDebugString with the message (from DebugView): [5936] Telerik Analytics Monitor ***** ERROR *****: Recovered session data could not be sent: 0 Request failed: NameResolutionFailure: No se puede resolver el nombre remoto: '27006a8622544e43b0da60db63bd66ba.monitor-telerik.com (http://27006a8622544e43b0da60db63bd66ba.monitor-telerik.com/) ' There seem to be about 8 messages a second. This makes debugging other applications that use OutputDebugString almost impossible if Fiddler is running.