diff --git a/tui_gateway/server.py b/tui_gateway/server.py
index a654d690496..4eb4a1b2ff9 100644
--- a/tui_gateway/server.py
+++ b/tui_gateway/server.py
@@ -9126,8 +9126,13 @@ def _(rid, params: dict) -> dict:
             "-f", str(first_page), "-l", str(last_page),
             str(pdf_path), str(out_prefix),
         ]
+        from hermes_cli._subprocess_compat import windows_hide_flags
+
         try:
-            res = subprocess.run(argv, capture_output=True, text=True, timeout=120, stdin=subprocess.DEVNULL)
+            res = subprocess.run(
+                argv, capture_output=True, text=True, timeout=120, stdin=subprocess.DEVNULL,
+                creationflags=windows_hide_flags(),
+            )
         except subprocess.TimeoutExpired:
             return _err(rid, 5028, "pdftoppm timed out (>120s)")
         if res.returncode != 0: