diff --git a/config/example.json b/config/example.json
index 8adea5b..89fa133 100644
--- a/config/example.json
+++ b/config/example.json
@@ -14,7 +14,7 @@
     {
       "id": "example",
       "name": "Example Upstream",
-      "uri": "file://C:\\site"
+      "uri": "files://./test/benchmark/data"
     }
   ]
 }
\ No newline at end of file
diff --git a/pkg/sign/responder.go b/pkg/sign/responder.go
index b2a8037..c2172fd 100644
--- a/pkg/sign/responder.go
+++ b/pkg/sign/responder.go
@@ -62,10 +62,9 @@ func makeFileResponse(ctx *fiber.Ctx, upstream *UpstreamConfig) error {
 			file, err = root.Open(queries.Get("fallback"))
 		}
 	}
-
 	if err != nil {
 		if errors.Is(err, fs.ErrNotExist) {
-			return ctx.Status(fiber.StatusNotFound).Next()
+			return fiber.ErrNotFound
 		}
 		return fmt.Errorf("failed to open: %w", err)
 	}
@@ -77,7 +76,8 @@ func makeFileResponse(ctx *fiber.Ctx, upstream *UpstreamConfig) error {
 
 	// Serve index if path is directory
 	if stat.IsDir() {
-		indexPath := utils.TrimRight(path, '/') + queries.Get("index")
+		indexFile := lo.Ternary(len(queries.Get("index")) > 0, queries.Get("index"), "index.html")
+		indexPath := utils.TrimRight(path, '/') + indexFile
 		index, err := root.Open(indexPath)
 		if err == nil {
 			indexStat, err := index.Stat()
@@ -105,7 +105,6 @@ func makeFileResponse(ctx *fiber.Ctx, upstream *UpstreamConfig) error {
 		ctx.Set(fiber.HeaderLastModified, modTime.UTC().Format(http.TimeFormat))
 	}
 
-	// Set Cache-Control header
 	if method == fiber.MethodGet {
 		maxAge, err := strconv.Atoi(queries.Get("maxAge"))
 		if lo.Ternary(err != nil, maxAge, 0) > 0 {
@@ -124,5 +123,5 @@ func makeFileResponse(ctx *fiber.Ctx, upstream *UpstreamConfig) error {
 		return nil
 	}
 
-	return ctx.Next()
+	return fiber.ErrNotFound
 }