diff --git a/server/api/files/preview.ts b/server/api/files/preview.ts
index 4d7f68c..1b7d8c5 100644
--- a/server/api/files/preview.ts
+++ b/server/api/files/preview.ts
@@ -37,6 +37,12 @@ export default defineEventHandler(async (event) => {
     // Generate presigned URL for preview
     const url = await getPreviewUrl(fileName, contentType);
     
+    console.log('Preview URL generated:', {
+      fileName,
+      contentType,
+      url: url.substring(0, 100) + '...' // Log first 100 chars for security
+    });
+    
     return {
       success: true,
       url,
diff --git a/server/utils/minio.ts b/server/utils/minio.ts
index 2b7c9d8..fdf1dda 100644
--- a/server/utils/minio.ts
+++ b/server/utils/minio.ts
@@ -26,16 +26,17 @@ export const listFiles = async (prefix: string = '', recursive: boolean = false)
     try {
       const stream = client.listObjectsV2(bucketName, prefix, recursive);
       
-      console.log(`Starting listObjectsV2 with prefix: "${prefix}", recursive: ${recursive}`);
-      
       stream.on('data', (obj) => {
-        // Skip objects without a name
-        if (!obj || typeof obj.name !== 'string') {
-          console.log('Skipping invalid object:', obj);
+        // Handle folder prefixes returned by MinIO
+        if (obj && obj.prefix) {
+          folders.add(obj.prefix);
           return;
         }
         
-        console.log(`Object received: "${obj.name}", size: ${obj.size}, etag: ${obj.etag}`);
+        // Skip objects without a name
+        if (!obj || typeof obj.name !== 'string') {
+          return;
+        }
         
         if (!recursive) {
           if (prefix) {