diff --git a/mnemo_cards_backend/lib/api/v2/admin_cards_api_v2.dart b/mnemo_cards_backend/lib/api/v2/admin_cards_api_v2.dart
index 00165dc..bdc3b60 100644
--- a/mnemo_cards_backend/lib/api/v2/admin_cards_api_v2.dart
+++ b/mnemo_cards_backend/lib/api/v2/admin_cards_api_v2.dart
@@ -674,11 +674,24 @@ class AdminCardsApiV2 {
       return _json(SuccessResponse(success: true).toJson());
     } catch (e, s) {
       print('Error in updateCard: $e\n$s');
+      
+      // Check for common database errors
+      final errorMessage = e.toString().toLowerCase();
+      String details = 'An unexpected error occurred while updating the card.';
+      
+      if (errorMessage.contains('constraint') || errorMessage.contains('unique')) {
+        details = 'A card with similar data may already exist. Please check for duplicates.';
+      } else if (errorMessage.contains('foreign key') || errorMessage.contains('pack')) {
+        details = 'The specified pack ID may be invalid. Please verify that the pack exists.';
+      } else if (errorMessage.contains('null') || errorMessage.contains('required')) {
+        details = 'Required fields are missing or invalid. Please check all required fields are provided.';
+      }
+      
       return _json(
         ErrorResponse(
           error: 'Internal server error',
           message: 'Failed to update card',
-          details: 'An unexpected error occurred while updating the card. Please try again later.',
+          details: details,
         ).toJson(),
         statusCode: 500,
       );
diff --git a/mnemo_cards_backend/lib/api/v2/packs_api_v2.dart b/mnemo_cards_backend/lib/api/v2/packs_api_v2.dart
index 80ea829..55bfca8 100644
--- a/mnemo_cards_backend/lib/api/v2/packs_api_v2.dart
+++ b/mnemo_cards_backend/lib/api/v2/packs_api_v2.dart
@@ -156,12 +156,18 @@ class PacksApiV2 {
     if (!_isValidUuid(value)) return null;
 
     try {
-      return await _minioService.getPresignedUrl(
+      final url = await _minioService.getPresignedUrl(
         bucket: bucket,
         objectId: value,
       );
-    } catch (e) {
-      print('Error generating presigned URL for $bucket/$value: $e');
+      if (url == null) {
+        print('⚠️ Warning: Failed to generate presigned URL for $bucket/$value - object may not exist in MinIO');
+      } else {
+        print('✅ Generated presigned URL for $bucket/$value (expires in ${MinioConfig.presignedUrlExpirySeconds}s)');
+      }
+      return url;
+    } catch (e, s) {
+      print('❌ Error generating presigned URL for $bucket/$value: $e\n$s');
       return null;
     }
   }
diff --git a/mnemo_cards_backend/lib/storage/minio_service.dart b/mnemo_cards_backend/lib/storage/minio_service.dart
index 3f87d0b..bf29a34 100644
--- a/mnemo_cards_backend/lib/storage/minio_service.dart
+++ b/mnemo_cards_backend/lib/storage/minio_service.dart
@@ -93,7 +93,7 @@ class MinioService {
   ///
   /// [bucket] - The bucket name
   /// [objectId] - The object ID (UUID)
-  /// [expirySeconds] - Optional expiry time in seconds (default: 4 hours)
+  /// [expirySeconds] - Optional expiry time in seconds (default: 7 days)
   ///
   /// Returns the presigned URL, or null if the object doesn't exist
   Future<String?> getPresignedUrl({
@@ -101,6 +101,7 @@ class MinioService {
     required String objectId,
     int? expirySeconds,
   }) async {
+    final expiry = expirySeconds ?? MinioConfig.presignedUrlExpirySeconds;
     try {
       // Check if object exists
       await _client.statObject(bucket, objectId);
@@ -109,13 +110,19 @@ class MinioService {
       final url = await _client.presignedGetObject(
         bucket,
         objectId,
-        expires: expirySeconds ?? MinioConfig.presignedUrlExpirySeconds,
+        expires: expiry,
       );
 
+      print('✅ Generated presigned URL for $bucket/$objectId (expires in ${expiry}s)');
       return url;
-    } catch (e) {
+    } on MinioException catch (e) {
       print(
-        '⚠️ Warning: Failed to generate presigned URL for $bucket/$objectId: $e',
+        '❌ MinIO error generating presigned URL for $bucket/$objectId: ${e.code} - ${e.message}',
+      );
+      return null;
+    } catch (e, s) {
+      print(
+        '❌ Unexpected error generating presigned URL for $bucket/$objectId: $e\n$s',
       );
       return null;
     }