diff --git a/pkg/notifications/smtp/smtp_test.go b/pkg/notifications/smtp/smtp_test.go
index 9096d1f5..d4c609f7 100644
--- a/pkg/notifications/smtp/smtp_test.go
+++ b/pkg/notifications/smtp/smtp_test.go
@@ -1,14 +1,8 @@
 package smtp
 
 import (
-	"errors"
-	"fmt"
-	"io"
-	"strings"
 	"testing"
 
-	smtp "github.com/emersion/go-smtp"
-
 	"github.com/jenkinsci/kubernetes-operator/api/v1alpha2"
 	"github.com/jenkinsci/kubernetes-operator/pkg/notifications/event"
 	"github.com/jenkinsci/kubernetes-operator/pkg/notifications/reason"
@@ -18,92 +12,7 @@ import (
 	"sigs.k8s.io/controller-runtime/pkg/client/fake"
 )
 
-const (
-	testSMTPUsername = "username"
-	testSMTPPassword = "password"
-
-	testSMTPPort = 1025
-
-	testFrom    = "test@localhost"
-	testTo      = "test.to@localhost"
-	testSubject = "Jenkins Operator Notification"
-
-	fromHeader    = "From"
-	toHeader      = "To"
-	subjectHeader = "Subject"
-
-	nilConst = "nil"
-)
-
-var (
-	testPhase     = event.PhaseUser
-	testCrName    = "test-cr"
-	testNamespace = "default"
-	testReason    = reason.NewPodRestart(
-		reason.KubernetesSource,
-		[]string{"test-reason-1"},
-		[]string{"test-verbose-1"}...,
-	)
-	testLevel = v1alpha2.NotificationLevelWarning
-)
-
-type testServer struct {
-	event event.Event
-}
-
-func (t *testServer) NewSession(c *smtp.Conn) (smtp.Session, error) {
-	return &testSession{event: t.event}, nil
-}
-
-func (bkd *testServer) Login(_ *smtp.Conn, username, password string) (smtp.Session, error) {
-	if username != testSMTPUsername || password != testSMTPPassword {
-		return nil, errors.New("invalid username or password")
-	}
-	return &testSession{event: bkd.event}, nil
-}
-
-type testSession struct {
-	event event.Event
-}
-
-func (s *testSession) Mail(from string, opts *smtp.MailOptions) error {
-	if from != testFrom {
-		return fmt.Errorf("from header mismatch: got %s expected %s", from, testFrom)
-	}
-	return nil
-}
-
-func (s *testSession) Rcpt(to string, opts *smtp.RcptOptions) error {
-	if to != testTo {
-		return fmt.Errorf("to header mismatch: got %s expected %s", to, testTo)
-	}
-	return nil
-}
-
-func (s *testSession) Data(r io.Reader) error {
-	b, err := io.ReadAll(r)
-	if err != nil {
-		return err
-	}
-
-	content := string(b)
-
-	if !strings.Contains(content, s.event.Jenkins.Name) {
-		return fmt.Errorf("jenkins name missing in email")
-	}
-
-	if !strings.Contains(content, string(s.event.Phase)) {
-		return fmt.Errorf("phase missing in email")
-	}
-
-	return nil
-}
-
-func (s *testSession) Reset() {}
-
-func (s *testSession) Logout() error {
-	return nil
-}
+const nilConst = "nil"
 
 func TestGenerateMessage(t *testing.T) {
 	t.Run("happy", func(t *testing.T) {
@@ -175,4 +84,39 @@ func TestGenerateMessage(t *testing.T) {
 		message := s.generateMessage(e)
 		assert.NotNil(t, message)
 	})
+
+	t.Run("with empty strings", func(t *testing.T) {
+		crName := ""
+		phase := event.PhaseBase
+		level := v1alpha2.NotificationLevelInfo
+		res := reason.NewUndefined(reason.KubernetesSource, []string{""}, []string{""}...)
+
+		from := ""
+		to := ""
+
+		e := event.Event{
+			Jenkins: v1alpha2.Jenkins{
+				ObjectMeta: metav1.ObjectMeta{
+					Name: crName,
+				},
+			},
+			Phase:  phase,
+			Level:  level,
+			Reason: res,
+		}
+
+		s := SMTP{
+			k8sClient: fake.NewClientBuilder().Build(),
+			config: v1alpha2.Notification{
+				LoggingLevel: level,
+				SMTP: &v1alpha2.SMTP{
+					From: from,
+					To:   to,
+				},
+			},
+		}
+
+		message := s.generateMessage(e)
+		assert.NotNil(t, message)
+	})
 }