I am new to C# and having to take sample code for encrypting ICVerify transactions for credit card processing. Below is a copy of the code but I am getting an error of " Error 1 Member 'ConsoleApplication1.EncryptionManager.EncryptThirdPartyMessage(string, string)' cannot be accessed with an instance reference; qualify it with a type name instead C:\Documents and Settings\relosegui\my documents\visual studio 2010\Projects\EncryptMe\EncryptMe\Encrypt.cs 45 40 EncryptMe" for the code highlighted in pink Can anyone offer assistance as to what may be my problem may be? Code: namespace ConsoleApplication1 { public class EncryptionManager { [DllImport("EncryptionManager.dll")] public static extern string EncryptThirdPartyMessage(string filePath, string stringToEncrypt); } class Program { static void Main(string[] args) { // File name format that ICVERIFY understand for request processing string csFileName = "\\icver001.out"; // Shared directory path where file is being created. string txtSharedDirPath = "C:\\Prod"; string csSharedDirPath = txtSharedDirPath + csFileName; /* // Request directory path where file will be used by // ICVERIFY for transaction processing. */ string txtReqPath = "C:\\ICVERIFY\\ICWin404\\ICPool"; string csReqPreparationPath = txtReqPath + csFileName; // Object of StreamWriter StreamWriter objWriter = null; // This code is creating an empty file in shared directory path FileStream objFileStream = new FileStream(csSharedDirPath, FileMode.Create, FileAccess.Write); objWriter = new StreamWriter(objFileStream); /* // To call EncryptionManager.dll to encrypt string // EncryptionManager.dll will use the creation date of the // file that was being created in shared directory path. */ string csStringToEncrypt = "Some string"; EncryptionManager objEncryptionManager = new EncryptionManager(); string csEncryptedString = objEncryptionManager.EncryptThirdPartyMessage(csSharedDirPath, csStringToEncrypt); // To write the encrypted string in the file objWriter.WriteLine(csEncryptedString); if (objWriter != null) objWriter.Close(); /* // Once all the encrypt strings have been written in file, // move that file into the request directory for processing. */ File.Move(csSharedDirPath, csReqPreparationPath); } } }