diff --git a/messenger/pinpoint.go b/messenger/pinpoint.go
index 3e29df5..fd93abc 100644
--- a/messenger/pinpoint.go
+++ b/messenger/pinpoint.go
@@ -94,22 +94,23 @@ func NewPinpoint(cfg []byte, l *onelog.Logger) (Messenger, error) {
 	if c.AppID == "" {
 		return nil, fmt.Errorf("invalid app_id")
 	}
-	if c.Region == "" {
-		return nil, fmt.Errorf("invalid region")
+
+	config := &aws.Config{
+		MaxRetries: aws.Int(3),
 	}
-	if c.AccessKey == "" {
-		return nil, fmt.Errorf("invalid access_key")
+	if c.AccessKey != "" && c.SecretKey != "" {
+		config.Credentials = credentials.NewStaticCredentials(c.AccessKey, c.SecretKey, "")
 	}
-	if c.SecretKey == "" {
-		return nil, fmt.Errorf("invalid secret_key")
+	if c.Region != "" {
+		config.Region = &c.Region
 	}
 
-	sess := session.Must(session.NewSession())
-	svc := pinpoint.New(sess,
-		aws.NewConfig().
-			WithCredentials(credentials.NewStaticCredentials(c.AccessKey, c.SecretKey, "")).
-			WithRegion(c.Region),
-	)
+	var sess = session.Must(session.NewSession(config))
+	err := checkCredentials(sess)
+	if err != nil {
+		return nil, err
+	}
+	svc := pinpoint.New(sess)
 
 	return pinpointMessenger{
 		client: svc,
diff --git a/messenger/ses.go b/messenger/ses.go
index b18db7a..39ee286 100644
--- a/messenger/ses.go
+++ b/messenger/ses.go
@@ -8,6 +8,7 @@ import (
 	"github.com/aws/aws-sdk-go/aws/credentials"
 	"github.com/aws/aws-sdk-go/aws/session"
 	"github.com/aws/aws-sdk-go/service/ses"
+	"github.com/aws/aws-sdk-go/service/sts"
 	"github.com/francoispqt/onelog"
 	"github.com/knadh/smtppool"
 )
@@ -106,6 +107,15 @@ func (s sesMessenger) Close() error {
 	return nil
 }
 
+func checkCredentials(sess *session.Session) error {
+	// Create a SES service client.
+	svc := sts.New(sess)
+	// Call the GetCallerIdentity API to check credentials
+	params := &sts.GetCallerIdentityInput{}
+	_, err := svc.GetCallerIdentity(params)
+	return err
+}
+
 // NewAWSSES creates new instance of pinpoint
 func NewAWSSES(cfg []byte, l *onelog.Logger) (Messenger, error) {
 	var c sesCfg
@@ -113,23 +123,23 @@ func NewAWSSES(cfg []byte, l *onelog.Logger) (Messenger, error) {
 		return nil, err
 	}
 
-	if c.Region == "" {
-		return nil, fmt.Errorf("invalid region")
+	config := &aws.Config{
+		MaxRetries: aws.Int(3),
 	}
-	if c.AccessKey == "" {
-		return nil, fmt.Errorf("invalid access_key")
+	if c.AccessKey != "" && c.SecretKey != "" {
+		config.Credentials = credentials.NewStaticCredentials(c.AccessKey, c.SecretKey, "")
 	}
-	if c.SecretKey == "" {
-		return nil, fmt.Errorf("invalid secret_key")
+	if c.Region != "" {
+		config.Region = &c.Region
 	}
 
-	sess := session.Must(session.NewSession())
-	svc := ses.New(sess,
-		aws.NewConfig().
-			WithCredentials(credentials.NewStaticCredentials(c.AccessKey, c.SecretKey, "")).
-			WithRegion(c.Region),
-	)
+	var sess = session.Must(session.NewSession(config))
+	err := checkCredentials(sess)
+	if err != nil {
+		return nil, err
+	}
 
+	svc := ses.New(sess)
 	return sesMessenger{
 		client: svc,
 		cfg:    c,