diff --git a/comfy_execution/jobs.py b/comfy_execution/jobs.py
index 4e5bd4273..6597fb0b2 100644
--- a/comfy_execution/jobs.py
+++ b/comfy_execution/jobs.py
@@ -10,9 +10,8 @@ class JobStatus:
     IN_PROGRESS = 'in_progress'
     COMPLETED = 'completed'
     FAILED = 'failed'
-    CANCELLED = 'cancelled'
 
-    ALL = [PENDING, IN_PROGRESS, COMPLETED, FAILED, CANCELLED]
+    ALL = [PENDING, IN_PROGRESS, COMPLETED, FAILED]
 
 
 # Media types that can be previewed in the frontend
@@ -86,7 +85,7 @@ def normalize_history_item(prompt_id, history_item, include_outputs=False):
     else:
         status = JobStatus.COMPLETED
 
-    outputs = history_item.get('outputs', {})
+    outputs = history_item.get('outputs') or {}
     outputs_count, preview_output = get_outputs_summary(outputs)
 
     execution_error = None
@@ -150,6 +149,8 @@ def get_outputs_summary(outputs):
                 continue
 
             for item in items:
+                if not isinstance(item, dict):
+                    continue
                 count += 1
 
                 if preview_output is None and is_previewable(media_type, item):
diff --git a/server.py b/server.py
index 65a25fd16..140f69c48 100644
--- a/server.py
+++ b/server.py
@@ -703,20 +703,23 @@ class PromptServer():
             status_param = query.get("status", None)
             status_filter = None
             if status_param:
-                status_filter = [s.strip() for s in status_param.split(',') if s.strip()]
+                status_filter = [s.strip().lower() for s in status_param.split(',') if s.strip()]
                 valid_statuses = set(JobStatus.ALL)
-                status_filter = [s for s in status_filter if s in valid_statuses]
-                if not status_filter:
-                    status_filter = None
+                invalid_statuses = [s for s in status_filter if s not in valid_statuses]
+                if invalid_statuses:
+                    return web.json_response(
+                        {"error": f"Invalid status value(s): {', '.join(invalid_statuses)}. Valid values: {', '.join(JobStatus.ALL)}"},
+                        status=400
+                    )
 
-            sort_by = query.get('sort_by', 'created_at')
+            sort_by = query.get('sort_by', 'created_at').lower()
             if sort_by not in {'created_at', 'execution_duration'}:
                 return web.json_response(
                     {"error": "sort_by must be 'created_at' or 'execution_duration'"},
                     status=400
                 )
 
-            sort_order = query.get('sort_order', 'desc')
+            sort_order = query.get('sort_order', 'desc').lower()
             if sort_order not in {'asc', 'desc'}:
                 return web.json_response(
                     {"error": "sort_order must be 'asc' or 'desc'"},
diff --git a/tests/execution/test_jobs.py b/tests/execution/test_jobs.py
index b01d26ecc..bedd142e6 100644
--- a/tests/execution/test_jobs.py
+++ b/tests/execution/test_jobs.py
@@ -19,7 +19,6 @@ class TestJobStatus:
         assert JobStatus.IN_PROGRESS == 'in_progress'
         assert JobStatus.COMPLETED == 'completed'
         assert JobStatus.FAILED == 'failed'
-        assert JobStatus.CANCELLED == 'cancelled'
 
     def test_all_contains_all_statuses(self):
         """ALL should contain all status values."""
@@ -27,8 +26,7 @@ class TestJobStatus:
         assert JobStatus.IN_PROGRESS in JobStatus.ALL
         assert JobStatus.COMPLETED in JobStatus.ALL
         assert JobStatus.FAILED in JobStatus.ALL
-        assert JobStatus.CANCELLED in JobStatus.ALL
-        assert len(JobStatus.ALL) == 5
+        assert len(JobStatus.ALL) == 4
 
 
 class TestIsPreviewable: