Ocurrió una excepción: There is an error in XML document.

System.InvalidOperationException: There is an error in XML document. ---> System.InvalidOperationException: <Project xmlns='http://schemas.microsoft.com/developer/msbuild/2003'> was not expected
  at System.Xml.Serialization.XmlSerializationReaderInterpreter.ReadRoot (System.Xml.Serialization.XmlTypeMapping rootMap) [0x00000] 
  at System.Xml.Serialization.XmlSerializationReaderInterpreter.ReadRoot () [0x00000] 
  at System.Xml.Serialization.XmlSerializer.Deserialize (System.Xml.Serialization.XmlSerializationReader reader) [0x00000] --- End of inner exception stack trace ---

  at System.Xml.Serialization.XmlSerializer.Deserialize (System.Xml.Serialization.XmlSerializationReader reader) [0x00000] 
  at System.Xml.Serialization.XmlSerializer.Deserialize (System.Xml.XmlReader xmlReader) [0x00000] 
  at System.Xml.Serialization.XmlSerializer.Deserialize (System.IO.Stream stream) [0x00000] 
  at MonoDevelop.Prj2Make.SlnMaker.CreatePrjxFromCsproj (System.String csprojFileName, IProgressMonitor monitor) [0x00000]