3 files changed, 6 insertions, 4 deletions
diff --git a/services/mailer/sender/message_test.go b/services/mailer/sender/message_test.go
index 63d0bc349a..ae153ebf05 100644
--- a/services/mailer/sender/message_test.go
+++ b/services/mailer/sender/message_test.go
@@ -108,9 +108,9 @@ func extractMailHeaderAndContent(t *testing.T, mail string) (map[string]string,
 	}
 	content := strings.TrimSpace("boundary=" + parts[1])
 
-	hParts := strings.Split(parts[0], "\n")
+	hParts := strings.SplitSeq(parts[0], "\n")
 
-	for _, hPart := range hParts {
+	for hPart := range hParts {
 		parts := strings.SplitN(hPart, ":", 2)
 		hk := strings.TrimSpace(parts[0])
 		if hk != "" {
diff --git a/services/mailer/sender/smtp.go b/services/mailer/sender/smtp.go
index c53c3da997..8dc1b40b74 100644
--- a/services/mailer/sender/smtp.go
+++ b/services/mailer/sender/smtp.go
@@ -5,6 +5,7 @@ package sender
 
 import (
 	"crypto/tls"
+	"errors"
 	"fmt"
 	"io"
 	"net"
@@ -99,7 +100,7 @@ func (s *SMTPSender) Send(from string, to []string, msg io.WriterTo) error {
 	canAuth, options := client.Extension("AUTH")
 	if len(opts.User) > 0 {
 		if !canAuth {
-			return fmt.Errorf("SMTP server does not support AUTH, but credentials provided")
+			return errors.New("SMTP server does not support AUTH, but credentials provided")
 		}
 
 		var auth smtp.Auth
diff --git a/services/mailer/sender/smtp_auth.go b/services/mailer/sender/smtp_auth.go
index 260b12437b..c60e0dbfbb 100644
--- a/services/mailer/sender/smtp_auth.go
+++ b/services/mailer/sender/smtp_auth.go
@@ -4,6 +4,7 @@
 package sender
 
 import (
+	"errors"
 	"fmt"
 
 	"github.com/Azure/go-ntlmssp"
@@ -60,7 +61,7 @@ func (a *ntlmAuth) Start(server *smtp.ServerInfo) (string, []byte, error) {
 func (a *ntlmAuth) Next(fromServer []byte, more bool) ([]byte, error) {
 	if more {
 		if len(fromServer) == 0 {
-			return nil, fmt.Errorf("ntlm ChallengeMessage is empty")
+			return nil, errors.New("ntlm ChallengeMessage is empty")
 		}
 		authenticateMessage, err := ntlmssp.ProcessChallenge(fromServer, a.username, a.password, a.domainNeeded)
 		return authenticateMessage, err