diff --git a/ozgcloud-keycloak-operator/src/main/java/de/ozgcloud/operator/keycloak/realm/KeycloakRealmMapper.java b/ozgcloud-keycloak-operator/src/main/java/de/ozgcloud/operator/keycloak/realm/KeycloakRealmMapper.java
index f4d143c6397763f2e4819fecf60b89b15f2cf1cf..f256c5974ef6db14bd3a529d1ca257dfabd450c9 100644
--- a/ozgcloud-keycloak-operator/src/main/java/de/ozgcloud/operator/keycloak/realm/KeycloakRealmMapper.java
+++ b/ozgcloud-keycloak-operator/src/main/java/de/ozgcloud/operator/keycloak/realm/KeycloakRealmMapper.java
@@ -53,14 +53,14 @@ interface KeycloakRealmMapper {
 	}
 	
 	@Named("smtpServer")
-	 default Map<String, String> mapsmtpServer(OzgCloudKeycloakRealmSpec.KeycloakRealmSMTPServer server) {
+	 default Map<String, String> mapSmtpServer(OzgCloudKeycloakRealmSpec.KeycloakRealmSMTPServer server) {
 		Map<String, String> smtpServer = new HashMap<>();
 		smtpServer.put("host", server.getHost());
 		smtpServer.put("port", server.getPort());
 		smtpServer.put("user", server.getUser());
 		smtpServer.put("password", server.getPassword());
-		smtpServer.put("starttls", server.getStarttls().toString()); 
-		smtpServer.put("auth", server.getAuth().toString()); 
+		smtpServer.put("starttls", server.getStarttls()); 
+		smtpServer.put("auth", server.getAuth()); 
 		smtpServer.put("from", server.getFrom()); 
 		smtpServer.put("fromDisplayName", server.getFromDisplayName()); 
 		return smtpServer;
diff --git a/ozgcloud-keycloak-operator/src/main/java/de/ozgcloud/operator/keycloak/realm/OzgCloudKeycloakRealmSpec.java b/ozgcloud-keycloak-operator/src/main/java/de/ozgcloud/operator/keycloak/realm/OzgCloudKeycloakRealmSpec.java
index c92f9340d32ee6e75e5b4290780ec75f1ed9ca19..0c03103d0da34b7f1a9bfc5db69a41118c8a2568 100644
--- a/ozgcloud-keycloak-operator/src/main/java/de/ozgcloud/operator/keycloak/realm/OzgCloudKeycloakRealmSpec.java
+++ b/ozgcloud-keycloak-operator/src/main/java/de/ozgcloud/operator/keycloak/realm/OzgCloudKeycloakRealmSpec.java
@@ -56,17 +56,17 @@ class OzgCloudKeycloakRealmSpec {
 @AllArgsConstructor
 static class KeycloakRealmSMTPServer {
 
-	private String host;
+	
 
 	private String user;
-
+	private String host;
 	private String password;
 
 	private String port;
 
-	private Boolean starttls;
+	private String starttls;
 
-	private Boolean auth;
+	private String auth;
 
 	private String from;
 	
diff --git a/ozgcloud-keycloak-operator/src/test/java/de/ozgcloud/operator/keycloak/realm/KeycloakRealmMapperTest.java b/ozgcloud-keycloak-operator/src/test/java/de/ozgcloud/operator/keycloak/realm/KeycloakRealmMapperTest.java
index 9a090e539b31fe9935b1bc020cdb160b87774ea1..bc63886d0cf9b6ebb39900ab1d346cc04e1341b3 100644
--- a/ozgcloud-keycloak-operator/src/test/java/de/ozgcloud/operator/keycloak/realm/KeycloakRealmMapperTest.java
+++ b/ozgcloud-keycloak-operator/src/test/java/de/ozgcloud/operator/keycloak/realm/KeycloakRealmMapperTest.java
@@ -24,6 +24,7 @@
 package de.ozgcloud.operator.keycloak.realm;
 
 import static org.assertj.core.api.Assertions.*;
+import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
 
 import org.junit.jupiter.api.Test;
 import org.mapstruct.factory.Mappers;
@@ -99,16 +100,26 @@ class KeycloakRealmMapperTest {
 
 	@Test
 	void shouldContainSmtpServerKeysValues() {
-		var mapped = mapper.map(OzgCloudKeycloakRealmSpecTestFactory.create());
+		var mapped = mapper.map(KeycloakRealmSmtpServerTestFactory.create());
 		var mappedSmtpServer = mapped.getSmtpServer();
-		assertThat(mappedSmtpServer.get("host")).isEqualTo("host");
+		assertThat(mappedSmtpServer.get("host")).isEqualTo(KeycloakRealmSmtpServerTestFactory.SMTP_SERVER_HOST);
 		assertThat(mappedSmtpServer.get("port")).isEqualTo("432");
-		assertThat(mappedSmtpServer.get("password")).isEqualTo("psw");
-		assertThat(mappedSmtpServer.get("user")).isEqualTo("user");
-		assertThat(mappedSmtpServer.get("starttls")).isEqualTo("true");
-		assertThat(mappedSmtpServer.get("auth")).isEqualTo("true");
-		assertThat(mappedSmtpServer.get("from")).isEqualTo("test@test.de");
-		assertThat(mappedSmtpServer.get("fromDisplayName")).isEqualTo("displayed name");
+		assertThat(mappedSmtpServer.get("password")).isEqualTo(KeycloakRealmSmtpServerTestFactory.SMTP_SERVER_PASSWORD);
+		assertThat(mappedSmtpServer.get("user")).isEqualTo(KeycloakRealmSmtpServerTestFactory.SMTP_SERVER_USER);
+		assertThat(mappedSmtpServer.get("starttls")).isEqualTo(KeycloakRealmSmtpServerTestFactory.SMTP_SERVER_STARTTLS.toString());
+		assertThat(mappedSmtpServer.get("auth")).isEqualTo(KeycloakRealmSmtpServerTestFactory.SMTP_SERVER_AUTH.toString());
+		assertThat(mappedSmtpServer.get("from")).isEqualTo(KeycloakRealmSmtpServerTestFactory.SMTP_SERVER_FROM);
+		assertThat(mappedSmtpServer.get("fromDisplayName")).isEqualTo(KeycloakRealmSmtpServerTestFactory.SMTP_SERVER_FROM_DISPLAY_NAME);
 		
 	}	
+
+
+	@Test
+	void shouldNotThrowOnRealmWithoutSMTP() {
+		//create realm without SMTP Servr configs
+		OzgCloudKeycloakRealm realm = OzgCloudKeycloakRealmTestFactory.create();
+		assertDoesNotThrow(() -> mapper.map(realm.getSpec()));
+	}
+	
+
 }
diff --git a/ozgcloud-keycloak-operator/src/test/java/de/ozgcloud/operator/keycloak/realm/KeycloakRealmSmtpServerTestFactory.java b/ozgcloud-keycloak-operator/src/test/java/de/ozgcloud/operator/keycloak/realm/KeycloakRealmSmtpServerTestFactory.java
new file mode 100644
index 0000000000000000000000000000000000000000..737c2a8f07cd0c76d8b2593bdfd757ca5bf22c5f
--- /dev/null
+++ b/ozgcloud-keycloak-operator/src/test/java/de/ozgcloud/operator/keycloak/realm/KeycloakRealmSmtpServerTestFactory.java
@@ -0,0 +1,28 @@
+package de.ozgcloud.operator.keycloak.realm;
+
+import de.ozgcloud.operator.keycloak.realm.OzgCloudKeycloakRealmSpec.KeycloakRealmSMTPServer;
+
+public class KeycloakRealmSmtpServerTestFactory {
+
+    
+    public final static String SMTP_SERVER_PORT = "432";
+    public final static String  SMTP_SERVER_HOST = "host";
+    public final static String  SMTP_SERVER_FROM = "test@test.de";
+    public final static String  SMTP_SERVER_FROM_DISPLAY_NAME = "displayed name";
+    public final static String  SMTP_SERVER_USER = "user"; 
+    public final static String  SMTP_SERVER_PASSWORD = "psw";
+    public final static String SMTP_SERVER_AUTH = "true";
+    public final static String SMTP_SERVER_STARTTLS = "true";
+    public final static KeycloakRealmSMTPServer SMTP_SERVER = KeycloakRealmSMTPServer.builder().host(SMTP_SERVER_HOST).user(SMTP_SERVER_USER).
+	password(SMTP_SERVER_PASSWORD).port(SMTP_SERVER_PORT).starttls(SMTP_SERVER_STARTTLS).auth(SMTP_SERVER_AUTH).from(SMTP_SERVER_FROM).fromDisplayName(SMTP_SERVER_FROM_DISPLAY_NAME).build();
+    
+    public static OzgCloudKeycloakRealmSpec create() {
+		return createBuilder().build();
+	}
+
+	public static OzgCloudKeycloakRealmSpec.OzgCloudKeycloakRealmSpecBuilder createBuilder() {
+		return OzgCloudKeycloakRealmSpec.builder()
+				.smtpServer(SMTP_SERVER);
+	}
+    
+}
diff --git a/ozgcloud-keycloak-operator/src/test/java/de/ozgcloud/operator/keycloak/realm/OzgCloudKeycloakRealmSpecTestFactory.java b/ozgcloud-keycloak-operator/src/test/java/de/ozgcloud/operator/keycloak/realm/OzgCloudKeycloakRealmSpecTestFactory.java
index 2e6ab10f3e82705204bea964388db168312c5c58..78cd362278adbda6df82081d96c9cfd8c5607c9d 100644
--- a/ozgcloud-keycloak-operator/src/test/java/de/ozgcloud/operator/keycloak/realm/OzgCloudKeycloakRealmSpecTestFactory.java
+++ b/ozgcloud-keycloak-operator/src/test/java/de/ozgcloud/operator/keycloak/realm/OzgCloudKeycloakRealmSpecTestFactory.java
@@ -23,15 +23,11 @@
  */
 package de.ozgcloud.operator.keycloak.realm;
 
-import de.ozgcloud.operator.keycloak.realm.OzgCloudKeycloakRealmSpec.KeycloakRealmSMTPServer;
-
 public class OzgCloudKeycloakRealmSpecTestFactory {
 
 	public final static String DISPLAY_NAME = "TestDisplayName";
 	public final static boolean KEEP_AFTER_DELETE = false;
-	public final static KeycloakRealmSMTPServer SMTP_SERVER = KeycloakRealmSMTPServer.builder().host("host").user("user").
-	password("psw").port("432").starttls(true).auth(true).from("test@test.de").fromDisplayName("displayed name").build();
-
+	
 	public static OzgCloudKeycloakRealmSpec create() {
 		return createBuilder().build();
 	}
@@ -39,7 +35,6 @@ public class OzgCloudKeycloakRealmSpecTestFactory {
 	public static OzgCloudKeycloakRealmSpec.OzgCloudKeycloakRealmSpecBuilder createBuilder() {
 		return OzgCloudKeycloakRealmSpec.builder()
 				.keepAfterDelete(KEEP_AFTER_DELETE)
-				.displayName(DISPLAY_NAME)
-				.smtpServer(SMTP_SERVER);
+				.displayName(DISPLAY_NAME);
 	}
 }