diff --git a/download.go b/download.go
index ccbb0d7..493016b 100644
--- a/download.go
+++ b/download.go
@@ -191,17 +191,15 @@ func doDownload(downloadURL, destDir string) error {
 	if err != nil {
 		return fmt.Errorf("임시 추출 디렉토리 생성 실패: %w", err)
 	}
+	defer os.RemoveAll(tmpExtractDir)
 
 	if err := extractZip(tmpPath, tmpExtractDir); err != nil {
-		os.RemoveAll(tmpExtractDir)
 		return err
 	}
 
 	if err := moveContents(tmpExtractDir, destDir); err != nil {
-		os.RemoveAll(tmpExtractDir)
 		return fmt.Errorf("파일 이동 실패: %w", err)
 	}
-	os.RemoveAll(tmpExtractDir)
 	return nil
 }
 
diff --git a/main.go b/main.go
index 8c2d0a7..90c054f 100644
--- a/main.go
+++ b/main.go
@@ -58,7 +58,7 @@ func handleURI(rawURI string) error {
 		if _, statErr := os.Stat(gamePath); statErr == nil {
 			ret := msgBox("One of the plans", "서버에 연결할 수 없습니다.\n설치된 게임을 실행하시겠습니까?\n(업데이트 확인 불가)", mbYesNo|mbQ)
 			if ret == idYes {
-				cmd := exec.Command(gamePath, "-token", token)
+				cmd := exec.Command(gamePath)
 				cmd.Dir = gameDir
 				cmd.Env = append(os.Environ(), "A301_TOKEN="+token)
 				if err := cmd.Start(); err != nil {
@@ -86,7 +86,7 @@ func handleURI(rawURI string) error {
 		return err
 	}
 
-	cmd := exec.Command(gamePath, "-token", token)
+	cmd := exec.Command(gamePath)
 	cmd.Dir = gameDir
 	cmd.Env = append(os.Environ(), "A301_TOKEN="+token)
 	if err := cmd.Start(); err != nil {
diff --git a/protocol.go b/protocol.go
index 5cd370b..83f4e9e 100644
--- a/protocol.go
+++ b/protocol.go
@@ -156,8 +156,24 @@ func fetchServerInfo() (*downloadInfo, error) {
 }
 
 // redeemTicket exchanges a one-time launch ticket for a fresh JWT access token.
+// Retries up to 3 times with exponential backoff on transient errors.
 func redeemTicket(ticket string) (string, error) {
-	return redeemTicketFrom(redeemTicketURL, ticket)
+	const maxRetries = 3
+	var lastErr error
+	for i := range maxRetries {
+		token, err := redeemTicketFrom(redeemTicketURL, ticket)
+		if err == nil {
+			return token, nil
+		}
+		lastErr = err
+		// HTTP 4xx errors should not be retried
+		var noRetry *errNoRetry
+		if errors.As(err, &noRetry) {
+			return "", err
+		}
+		time.Sleep(time.Duration(1<<i) * time.Second)
+	}
+	return "", fmt.Errorf("인증 실패 (%d회 재시도): %w", maxRetries, lastErr)
 }
 
 func redeemTicketFrom(url, ticket string) (string, error) {
@@ -173,6 +189,9 @@ func redeemTicketFrom(url, ticket string) (string, error) {
 	}
 	defer resp.Body.Close()
 
+	if resp.StatusCode >= 400 && resp.StatusCode < 500 {
+		return "", &errNoRetry{fmt.Errorf("런처 인증에 실패했습니다 (HTTP %d)", resp.StatusCode)}
+	}
 	if resp.StatusCode != http.StatusOK {
 		return "", fmt.Errorf("런처 인증에 실패했습니다 (HTTP %d)", resp.StatusCode)
 	}