diff --git a/gateway/status.py b/gateway/status.py
index 4cdf8f8109..9e373564d4 100644
--- a/gateway/status.py
+++ b/gateway/status.py
@@ -496,7 +496,8 @@ def acquire_scoped_lock(scope: str, identity: str, metadata: Optional[dict[str,
         if not stale:
             try:
                 os.kill(existing_pid, 0)
-            except (ProcessLookupError, PermissionError):
+            except (ProcessLookupError, PermissionError, OSError):
+                # Windows raises OSError with WinError 87 for invalid pid check
                 stale = True
             else:
                 current_start = _get_process_start_time(existing_pid)
@@ -743,6 +744,10 @@ def get_running_pid(
             if _record_looks_like_gateway(record):
                 return pid
             continue
+        except OSError:
+            # Windows raises OSError with WinError 87 for an invalid pid
+            # (process is definitely gone). Treat as "process doesn't exist".
+            continue
 
         recorded_start = record.get("start_time")
         current_start = _get_process_start_time(pid)