diff --git a/.last-branch b/.last-branch
index 782eaef..f8987a1 100644
--- a/.last-branch
+++ b/.last-branch
@@ -1 +1 @@
-v20260115-04-autotask-reference-data-fix
+v20260115-05-autotask-queues-picklist-fix
diff --git a/containers/backupchecks/src/backend/app/integrations/autotask/client.py b/containers/backupchecks/src/backend/app/integrations/autotask/client.py
index 95eb90c..b82983c 100644
--- a/containers/backupchecks/src/backend/app/integrations/autotask/client.py
+++ b/containers/backupchecks/src/backend/app/integrations/autotask/client.py
@@ -163,10 +163,43 @@ class AutotaskClient:
         return self._as_items_list(data)
 
     def get_queues(self) -> List[Dict[str, Any]]:
-        return self._get_collection("Queues")
+        """Return Ticket Queue picklist values.
+
+        Autotask does not expose a universal top-level Queues entity in all tenants.
+        The reliable source is the Tickets.queueID picklist metadata.
+        """
+        return self._get_ticket_picklist_values(field_names=["queueid", "queue"])
 
     def get_ticket_sources(self) -> List[Dict[str, Any]]:
-        return self._get_collection("TicketSources")
+        """Return Ticket Source picklist values.
+
+        Similar to queues, Ticket Source values are best retrieved via the
+        Tickets.source picklist metadata to avoid relying on optional entities.
+        """
+        return self._get_ticket_picklist_values(field_names=["source", "sourceid"])
+
+    def _get_ticket_picklist_values(self, field_names: List[str]) -> List[Dict[str, Any]]:
+        fields = self._get_entity_fields("Tickets")
+        wanted = {n.strip().lower() for n in (field_names or []) if str(n).strip()}
+
+        field: Optional[Dict[str, Any]] = None
+        for f in fields:
+            name = str(f.get("name") or "").strip().lower()
+            if name in wanted:
+                field = f
+                break
+
+        if not field:
+            raise AutotaskError(f"Unable to locate Tickets field metadata for picklist retrieval: {sorted(wanted)}")
+
+        if not bool(field.get("isPickList")):
+            raise AutotaskError(f"Tickets.{field.get('name')} is not marked as a picklist in Autotask metadata.")
+
+        picklist_path = field.get("picklistValues")
+        if not isinstance(picklist_path, str) or not picklist_path.strip():
+            raise AutotaskError(f"Tickets.{field.get('name')} metadata did not include a picklistValues endpoint.")
+
+        return self._call_picklist_values(picklist_path)
 
     def get_ticket_priorities(self) -> List[Dict[str, Any]]:
         """Return Ticket Priority picklist values.
diff --git a/containers/backupchecks/src/backend/app/main/routes_settings.py b/containers/backupchecks/src/backend/app/main/routes_settings.py
index 1127187..5897121 100644
--- a/containers/backupchecks/src/backend/app/main/routes_settings.py
+++ b/containers/backupchecks/src/backend/app/main/routes_settings.py
@@ -1324,13 +1324,25 @@ def settings_autotask_refresh_reference_data():
         priorities = client.get_ticket_priorities()
 
         # Store a minimal subset for dropdowns (id + name/label)
+        # Note: Some "reference" values are exposed as picklists (value/label)
+        # instead of entity collections (id/name). We normalize both shapes.
         def _norm(items):
             out = []
             for it in items or []:
                 if not isinstance(it, dict):
                     continue
                 _id = it.get("id")
-                name = it.get("name") or it.get("label") or it.get("queueName") or it.get("sourceName") or it.get("description") or ""
+                if _id is None:
+                    _id = it.get("value")
+
+                name = (
+                    it.get("name")
+                    or it.get("label")
+                    or it.get("queueName")
+                    or it.get("sourceName")
+                    or it.get("description")
+                    or ""
+                )
                 try:
                     _id_int = int(_id)
                 except Exception:
diff --git a/docs/changelog.md b/docs/changelog.md
index 93888d6..161d863 100644
--- a/docs/changelog.md
+++ b/docs/changelog.md
@@ -36,6 +36,15 @@
 - Improved “Test connection” to validate authentication and reference data access reliably.
 - Fixed admin event logging to prevent secondary exceptions during error handling.
 
+## v20260115-05-autotask-queues-picklist-fix
+
+Changes:
+- Reworked Autotask reference data retrieval to use Ticket entity picklists instead of non-existent top-level resources.
+- Retrieved Queues via the Tickets.queueID picklist to ensure compatibility with all Autotask tenants.
+- Retrieved Ticket Sources via the Tickets.source picklist instead of a direct collection endpoint.
+- Kept Priority retrieval fully dynamic using the Tickets.priority picklist.
+- Normalized picklist values so IDs and display labels are handled consistently in settings dropdowns.
+- Fixed Autotask connection test to rely on picklist availability, preventing false 404 errors.
 
 ***