PROBLEMA AO CHAMAR FUNCAO DA DLL

using System;
using System.Configuration;
using System.Diagnostics;
using System.IO;
using System.Reflection;

namespace Wilcom.Engines.WDCEmbEngine
{
    public static class WDCEmbEngine
    {
        private static object syncLock;

        private static DllInterface dllInterface;

        public static string EngineDll
        {
            get
            {
                string text = ConfigurationManager.get_AppSettings()["EngineDLL"];
                if (Path.IsPathRooted(text))
                {
                    return text;
                }

                return Path.Combine(Environment.CurrentDirectory, text);
            }
        }

        public static string EngineVersion
        {
            get
            {
                FileVersionInfo versionInfo = FileVersionInfo.GetVersionInfo(EngineDll);
                return " (" + Path.GetFullPath(EngineDll) + ", ver " + versionInfo.ProductMajorPart + "." + versionInfo.ProductMinorPart + "." + versionInfo.ProductBuildPart + "." + versionInfo.ProductPrivatePart + ", " + File.GetLastWriteTime(EngineDll).ToString() + ")";
            }
        }

        static WDCEmbEngine()
        {
            syncLock = new object();
            string directoryName = Path.GetDirectoryName(EngineDll);
            string environmentVariable = Environment.GetEnvironmentVariable("PATH");
            string value = directoryName + ";" + environmentVariable;
            Environment.SetEnvironmentVariable("PATH", value);
            dllInterface = CreateDLLInterface();
        }

        private static DllInterface CreateDLLInterface()
        {
            string fileName = Path.GetFileName(EngineDll);
            Type[] types = typeof(DllInterface).Assembly.GetTypes();
            foreach (Type type in types)
            {
                if (type.IsSubclassOf(typeof(DllInterface)) && !type.IsAbstract)
                {
                    DllInterface dllInterface = type.GetConstructor(Type.EmptyTypes).Invoke(null) as DllInterface;
                    if (dllInterface.GetDllName().Equals(fileName, StringComparison.OrdinalIgnoreCase))
                    {
                        return dllInterface;
                    }
                }
            }

            throw new Exception("Unsupported engine dll name: " + fileName);
        }

        public static bool SupportsCreateDesign()
        {
            return dllInterface.SupportsCreateDesign();
        }

        public static XmlEngineInfo GetEngineInfo()
        {
            object[] array = new object[1];
            CallEngineAPI("WDCEmbEngine_GetEngineInfo", array);
            XmlEngineInfo xmlEngineInfo = StringXmlSerializer.Deserialize<XmlEngineInfo>(array[0] as string);
            FileVersionInfo versionInfo = FileVersionInfo.GetVersionInfo(EngineDll);
            xmlEngineInfo.engine_info.engine_version = new engine_version
            {
                major = versionInfo.ProductMajorPart,
                minor = versionInfo.ProductMinorPart,
                build = versionInfo.ProductBuildPart,
                privat = versionInfo.ProductPrivatePart
            };
            return xmlEngineInfo;
        }

        public static XmlDesignInfo GetDesignInfo(string designFilename)
        {
            object[] array = new object[2] { designFilename, null };
            CallEngineAPI("WDCEmbEngine_GetDesignInfo", array);
            return StringXmlSerializer.Deserialize<XmlDesignInfo>(array[1] as string);
        }

        public static XmlDesignInfo GetDesignInfoAndTrueview(string designFilename, int dpi)
        {
            object[] array = new object[3] { designFilename, null, dpi };
            CallEngineAPI("WDCEmbEngine_GetDesignInfoAndTrueview", array);
            return StringXmlSerializer.Deserialize<XmlDesignInfo>(array[1] as string);
        }

        public static XmlDesignInfo GetDesignInfoAndThumbnail(string designFilename)
        {
            object[] array = new object[2] { designFilename, null };
            CallEngineAPI("WDCEmbEngine_GetDesignInfoAndThumbnail", array);
            return StringXmlSerializer.Deserialize<XmlDesignInfo>(array[1] as string);
        }

        public static XmlDesignInfo GenerateTrueview(XmlEngineDocument xmlEngineDocument)
        {
            string text = StringXmlSerializer.Serialize(xmlEngineDocument);
            object[] array = new object[2] { text, null };
            CallEngineAPI("WDCEmbEngine_GenerateTrueview", array);
            return StringXmlSerializer.Deserialize<XmlDesignInfo>(array[1] as string);
        }

        public static XmlDesignInfo GenerateDesign(XmlEngineDocument xmlEngineDocument)
        {
            string text = StringXmlSerializer.Serialize(xmlEngineDocument);
            object[] array = new object[2] { text, null };
            CallEngineAPI("WDCEmbEngine_GenerateDesign", array);
            return StringXmlSerializer.Deserialize<XmlDesignInfo>(array[1] as string);
        }

        public static XmlDesignInfo GenerateLetteringPreview(XmlEngineDocument xmlEngineDocument)
        {
            string text = StringXmlSerializer.Serialize(xmlEngineDocument);
            object[] array = new object[2] { text, null };
            CallEngineAPI("WDCEmbEngine_GenerateLetteringPreview", array);
            return StringXmlSerializer.Deserialize<XmlDesignInfo>(array[1] as string);
        }

        private static void CallEngineAPI(string methodName, object[] methodParams)
        {
            lock (syncLock)
            {
                uint num = 0u;
                MethodInfo method = dllInterface.GetType().GetMethod(methodName, BindingFlags.Static | BindingFlags.NonPublic);
                if (method == null)
                {
                    throw new Exception("Method " + methodName + " cannot be found in " + dllInterface.GetDllName());
                }

                num = (uint)method.Invoke(null, methodParams);
                if (num != 0)
                {
                    throw new Exception("Call to " + methodName + " failed.
Return code: " + ErrorCodes.GetErrorCode(num));
                }
            }
        }
    }
}

            try
            {
  

            var temp = WDCEmbEngine.GetDesignInfo(@"D:\backup dados\clientes    este\SOLAR.EMB");
            }
            catch (Exception exception1)
            {
                Console.WriteLine(exception1.ToString());
            }