Send mail via SMTP c#

EMailHelper.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Net;
using System.Net.Mail;
using DomainClasses;
using System.IO;

namespace Helpers
{
    /// <summary>
    /// Class for Email Methods
    /// </summary>
    public class EmailHelper
    {
        /// <summary>
        /// Method to Send Mail
        /// </summary>
        /// <param name="email"></param>
        /// <returns>Error message in case of Error</returns>
        public static string SendMail(EmailModel email)
        {
            try
            {
                using (MailMessage mail = new MailMessage())
                {
                    mail.From = new MailAddress(email.EmailFrom);
                    mail.To.Add(email.EmailTo);
                    mail.Subject = email.Subject;
                    mail.Body = email.Body;
                    mail.IsBodyHtml=true;
                    //Way to add attachment
                    //mail.Attachments.Add(new Attachment("C:\\SomeFile.txt"));
                    using (SmtpClient smtp = new SmtpClient(email.SmtpAddress, email.PortNumber))
                    {
                        smtp.Credentials = new NetworkCredential(email.EmailFrom, email.Password);
                        smtp.EnableSsl = email.EnableSSL;
                        smtp.Send(mail);
                    }
                }
            }
            catch (SmtpFailedRecipientException exception)
            {
                Logger.Logger.Error("SMTP error in sending email", exception);
                return Utilities.ReturnException(exception);
            }
            catch (Exception ex)
            {
                Logger.Logger.Error("Error in Sending Email", ex);
                return Utilities.ReturnException(ex);
            }
            return string.Empty;
        }
    }
}