diff --git a/internal/user/smtp.go b/internal/user/smtp.go
index c2699ce1..b9f0c477 100644
--- a/internal/user/smtp.go
+++ b/internal/user/smtp.go
@@ -468,7 +468,7 @@ func getRecipients(
 	prefs, err := parallel.MapContext(ctx, runtime.NumCPU(), addresses, func(ctx context.Context, recipient string) (proton.SendPreferences, error) {
 		pubKeys, recType, err := client.GetPublicKeys(ctx, recipient)
 		if err != nil {
-			return proton.SendPreferences{}, fmt.Errorf("failed to get public keys: %w", err)
+			return proton.SendPreferences{}, fmt.Errorf("failed to get public keys: %w (%v)", err, recipient)
 		}
 
 		contactSettings, err := getContactSettings(ctx, client, userKR, recipient)