C#

public void coordHandler(double x, double y, double z, int buttonNumber)
{
   xCoord.Text = x.ToString();
   yCoord.Text = y.ToString();
   zCoord.Text = z.ToString();
}

MyCOMInterfaceLib.MyCOMClassClass myApi = new MyCOMInterfaceLib.MyCOMClassClass();
myApi.coordCallback += new coordCallbackFunction(this.coordHandler);

public class sheetCols
{
string colHdg;
public string colLetter;
public StringBuilder colValue = new StringBuilder(" ");
                  

    public sheetCols(string s1, string s2, string s3)   //error indicated on "sheetCols"
    {
         this.colHdg = s1;
         this.colLetter = s2;
         this.colValue.Length = 0; // warning indicated on this.colValue
         this.colValue.Append(s3);
    }
}

private void EncryptFile(string inputFile, string outputFile)
{

    try
    {
        string password = @"19651969"; // Your Key Here
        UnicodeEncoding UE = new UnicodeEncoding();
        byte[] key = UE.GetBytes(password);

        string cryptFile = outputFile;
        FileStream fsCrypt = new FileStream(cryptFile, FileMode.Create);

        RijndaelManaged RMCrypto = new RijndaelManaged();

        CryptoStream cs = new CryptoStream(fsCrypt,
            RMCrypto.CreateEncryptor(key, key),
            CryptoStreamMode.Write);

        FileStream fsIn = new FileStream(inputFile, FileMode.Open);

        int data;
        while ((data = fsIn.ReadByte()) != -1)
            cs.WriteByte((byte)data);


        fsIn.Close();
        cs.Close();
        fsCrypt.Close();
    }
    catch
    {
        MessageBox.Show("Encryption failed!", "Error");
    }
}

private void DecryptFile(string inputFile, string outputFile)
{

    {
        string password = @"19651969"; // Your Key Here

        UnicodeEncoding UE = new UnicodeEncoding();
        byte[] key = UE.GetBytes(password);

        FileStream fsCrypt = new FileStream(inputFile, FileMode.Open);

        RijndaelManaged RMCrypto = new RijndaelManaged();

        CryptoStream cs = new CryptoStream(fsCrypt,
            RMCrypto.CreateDecryptor(key, key),
            CryptoStreamMode.Read);

        FileStream fsOut = new FileStream(outputFile, FileMode.Create);

        int data;
        while ((data = cs.ReadByte()) != -1)
            fsOut.WriteByte((byte)data);

        fsOut.Close();
        cs.Close();
        fsCrypt.Close();

    }
}

private void Form1_Load(object sender, EventArgs e)
{

    if (File.Exists("scf.sf"))
    {
        DecryptFile("scf.sf", "sff.sf");
        File.Delete("scf.sf");
        File.Move("sff.sf", "scf.sf");

        TextReader encryptRead = new StreamReader("scf.sf");
        string encryptionCheck = encryptRead.ReadToEnd();
        encryptRead.Close();

        if (encryptionCheck.Contains("locked"))
        {
            MessageBox.Show("**yayaya***", "BlaBla", MessageBoxButtons.OK, MessageBoxIcon.Stop);

            EncryptFile("scf.sf", "ssf.sf");
            File.Delete("scf.sf");
            File.Move("ssf.sf", "scf.sf");

            Application.Exit();
        }
    }
    else
    {
        MessageBox.Show("Component Corrupt, Application Will Now End.", "Slyther Security Runtime", MessageBoxButtons.OK, MessageBoxIcon.Error);
        Application.Exit();
    }


    EncryptFile("slcf.sf", "slcfc.sf");
    File.Delete("slcf.sf");
    File.Move("slcfc.sf", "slcf.sf");

}

while ((data = cs.ReadByte()) != -1)

IndexOutOfRangeException was Unhandled.

Index was outside the bounds of the array.