System.Web.Services.Protocols.SoapException: WebRequestUnableToRead ---> System.InvalidOperationException: There is an error in XML document (2, 522). ---> System.FormatException: The string '' is not a valid AllXsd value.
  at System.Xml.Schema.XsdDateTime..ctor (System.String text, System.Xml.Schema.XsdDateTimeFlags kinds) [0x0003a] in <1140eab9e72948548294172a9716416d>:0 
  at System.Xml.XmlConvert.ToDateTime (System.String s, System.Xml.XmlDateTimeSerializationMode dateTimeOption) [0x00000] in <1140eab9e72948548294172a9716416d>:0 
  at System.Xml.Serialization.XmlCustomFormatter.ToDateTime (System.String value) [0x00017] in <1140eab9e72948548294172a9716416d>:0 
  at System.Xml.Serialization.XmlSerializationReader.ToDateTime (System.String value) [0x00000] in <1140eab9e72948548294172a9716416d>:0 
  at Microsoft.Xml.Serialization.GeneratedAssembly.XmlSerializationReader1.Read3_ProcessingData (System.Boolean isNullable, System.Boolean checkType) [0x0020a] in <d710309a74f64119b9c9b98cafa10932>:0 
  at Microsoft.Xml.Serialization.GeneratedAssembly.XmlSerializationReader1.Read9_AddDll () [0x00145] in <d710309a74f64119b9c9b98cafa10932>:0 
  at Microsoft.Xml.Serialization.GeneratedAssembly.ArrayOfObjectSerializer4.Deserialize (System.Xml.Serialization.XmlSerializationReader reader) [0x00000] in <d710309a74f64119b9c9b98cafa10932>:0 
  at System.Xml.Serialization.XmlSerializer.Deserialize (System.Xml.XmlReader xmlReader, System.String encodingStyle, System.Xml.Serialization.XmlDeserializationEvents events) [0x0007f] in <1140eab9e72948548294172a9716416d>:0 
   --- End of inner exception stack trace ---
  at System.Xml.Serialization.XmlSerializer.Deserialize (System.Xml.XmlReader xmlReader, System.String encodingStyle, System.Xml.Serialization.XmlDeserializationEvents events) [0x00139] in <1140eab9e72948548294172a9716416d>:0 
  at System.Xml.Serialization.XmlSerializer.Deserialize (System.Xml.XmlReader xmlReader, System.String encodingStyle) [0x00000] in <1140eab9e72948548294172a9716416d>:0 
  at System.Web.Services.Protocols.SoapServerProtocol.ReadParameters () [0x003e9] in <df933ee897464fb99338a340b9d5761d>:0 
   --- End of inner exception stack trace ---
  at System.Web.Services.Protocols.SoapServerProtocol.ReadParameters () [0x004a7] in <df933ee897464fb99338a340b9d5761d>:0 
  at System.Web.Services.Protocols.WebServiceHandler.CoreProcessRequest () [0x0014d] in <df933ee897464fb99338a340b9d5761d>:0 

Service.AddDll(FUsrname, pd, FarrByte, FResult, FID, FDateLoad);

FDateLoad := TXSDateTime.Create;
    FDateLoad.XSToNative('1900-01-01T00:00:00.000Z');

Service := GetProcessingDllSvcSoap(True);

        FUsrname := 'хххххххххх';
        FS.Position := 0;

        SetLength(FarrByte, FS.Size);
        FS.Read(FarrByte[0], FS.Size);

        pd.Info.DllName := ExtractFileName(ODDlls.FileName);
        pd.Info.DllVersion := PluginInfo.FileVersion;
        pd.Info.FileSize := FS.Size;
        pd.Desc := PluginInfo.ProductName;
        pd.Info.LastDateModified := DateTimeToXSDateTime(FileDateToDateTime(FileAge(ODDlls.FileName)));

        Service.AddDll(FUsrname, pd, FarrByte, FResult, FID, FDateLoad);