diff --git a/BTCPayServer/Services/Mails/EmailSettings.cs b/BTCPayServer/Services/Mails/EmailSettings.cs
index ce0b06b87..9cc258605 100644
--- a/BTCPayServer/Services/Mails/EmailSettings.cs
+++ b/BTCPayServer/Services/Mails/EmailSettings.cs
@@ -1,24 +1,16 @@
-using System.ComponentModel.DataAnnotations;
-using System.Net;
-using System.Net.Security;
-using System.Security.Cryptography.X509Certificates;
 using System.Threading;
 using System.Threading.Tasks;
 using BTCPayServer.Client.Models;
 using MailKit.Net.Smtp;
 using MimeKit;
-using Newtonsoft.Json;
 
 namespace BTCPayServer.Services.Mails
 {
-    public class EmailSettings :EmailSettingsData
+    public class EmailSettings : EmailSettingsData
     {
         public bool IsComplete()
         {
-            return !string.IsNullOrWhiteSpace(Server) &&
-                   Port is int &&
-                   !string.IsNullOrWhiteSpace(Login) &&
-                   !string.IsNullOrWhiteSpace(Password);
+            return !string.IsNullOrWhiteSpace(Server) && Port is int;
         }
 
         public MimeMessage CreateMailMessage(MailboxAddress to, string subject, string message, bool isHtml)
@@ -54,7 +46,8 @@ namespace BTCPayServer.Services.Mails
 #pragma warning restore CA5359 // Do Not Disable Certificate Validation
                 }
                 await client.ConnectAsync(Server, Port.Value, MailKit.Security.SecureSocketOptions.Auto, connectCancel.Token);
-                await client.AuthenticateAsync(Login, Password, connectCancel.Token);
+                if ((client.Capabilities & SmtpCapabilities.Authentication) != 0)
+                    await client.AuthenticateAsync(Login ?? string.Empty, Password ?? string.Empty, connectCancel.Token);
             }
             catch
             {