diff --git a/nanobot/agent/memory.py b/nanobot/agent/memory.py
index 26c5cd45f..e9662ff2c 100644
--- a/nanobot/agent/memory.py
+++ b/nanobot/agent/memory.py
@@ -290,7 +290,7 @@ class MemoryStore:
                 if not lines:
                     return None
                 return json.loads(lines[-1])
-        except (FileNotFoundError, json.JSONDecodeError):
+        except (FileNotFoundError, json.JSONDecodeError, UnicodeDecodeError):
             return None
 
     def _write_entries(self, entries: list[dict[str, Any]]) -> None: