Password Validation Method in C#

// needs: using System; using System.Text.RegularExpressions;
public static bool ValidatePassword(string password, out string ErrorMessage)
{
    bool reqUpperCaseLetter = true;
    bool reqLowerCaseLetter = false;
    bool reqDecimalDigit = false;
    bool reqSpecialChar = false;
    var input = password;
    ErrorMessage = string.Empty;
    if (string.IsNullOrWhiteSpace(input))
    {
        throw new Exception("Password should not be empty");
    }
    var hasNumber = new Regex(@"[0-9]+");
    var hasUpperChar = new Regex(@"[A-Z]+");
    var hasMiniMaxChars = new Regex(@".{8,15}");
    var hasLowerChar = new Regex(@"[a-z]+");
    var hasSymbols = new Regex(@"[!@#$%^&*()_+=\[{\]};:<>|./?,-]");
    if (!hasLowerChar.IsMatch(input) && reqLowerCaseLetter ==true)
    {
        ErrorMessage = "Password should contain at least one lower case letter.";
        return false;
    }
    else if (!hasUpperChar.IsMatch(input) && reqUpperCaseLetter ==true)
    {
        ErrorMessage = "Password should contain at least one upper case letter.";
        return false;
    }
    else if (!hasMiniMaxChars.IsMatch(input))
    {
        ErrorMessage = "Password should not be lesser than 8 or greater than 15 characters.";
        return false;
    }
    else if (!hasNumber.IsMatch(input) && reqDecimalDigit==false)
    {
        ErrorMessage = "Password should contain at least one numeric value.";
        return false;
    }
    else if (!hasSymbols.IsMatch(input) && reqSpecialChar ==false)
    {
        ErrorMessage = "Password should contain at least one special case character.";
        return false;
    }
    else
    {
        ErrorMessage = "Success";
        return true;
    }
}