WinFrom:

public static string StringToMD5Hash(string inputString)

{

    MD5CryptoServiceProvider md5 = new MD5CryptoServiceProvider();

    byte[] encryptedBytes = md5.ComputeHash(Encoding.ASCII.GetBytes(inputString));

    StringBuilder sb = new StringBuilder();

    for (int i = 0; i < encryptedBytes.Length; i++)

    {

        sb.AppendFormat("{0:x2}", encryptedBytes[i]);

    }

    return sb.ToString();

}

WebFrom:

public static string md5(string pwd)
{
    string md5pwd = FormsAuthentication.HashPasswordForStoringInConfigFile(pwd, "MD5");
    return md5pwd;
}