diff --git a/prepare_pages_and_registry.py b/prepare_pages_and_registry.py
index d97282a..52416d2 100644
--- a/prepare_pages_and_registry.py
+++ b/prepare_pages_and_registry.py
@@ -29,8 +29,42 @@ IS_REDIRECT_RE = re.compile(r'"wgIsRedirect"\s*:\s*true')
 NAMESPACE_RE = re.compile(r'"wgCanonicalNamespace"\s*:\s*"([^"]*)"')
 WG_TITLE_RE = re.compile(r'"wgTitle"\s*:\s*"([^"]+)"')
 SHORT_SLUG_RE = re.compile(r"^[a-z0-9]+[0-9]*$")
-
 UNICODE_ESCAPE_RE = re.compile(r'\\u([0-9a-fA-F]{4})')
+ERROR_PAGE_PATTERNS = [
+    # 5xx
+    "503 service unavailable",
+    "502 bad gateway",
+    "500 internal server error",
+    "504 gateway time",
+
+    # 4xx
+    "400 bad request",
+    "401 unauthorized",
+    "403 forbidden",
+    "404 not found",
+    "408 request time",
+    "419 page expired",
+    "429 too many requests",
+
+    # génériques
+    "temporarily busy",
+    "server error",
+    "internal error",
+    "page not found",
+    "request could not be satisfied",
+]
+
+def is_error_page(page_html: str) -> bool:
+    text = page_html.lower()
+
+    if "<html" not in text:
+        return False
+
+    for pattern in ERROR_PAGE_PATTERNS:
+        if pattern in text:
+            return True
+
+    return False
 
 def decode_mediawiki_string(s: str) -> str:
     if not s:
@@ -177,7 +211,24 @@ for i, path in enumerate(files, 1):
 
         article_id = extract_article_id(page_html)
         if not article_id:
-            ignored_pages.append(path.name)
+            if not is_error_page(page_html):
+                ignored_pages.append(path.name)
+                continue
+
+            fake_title = normalize_title(path.stem)
+
+            all_variants[f"error::{fake_title}"].append({
+                "path": path,
+                "title": fake_title,
+                "canonical_key": fake_title,
+                "article_id": None,
+                "wg_title": None,
+                "redirect": False,
+                "is_category": False,
+                "is_listing_only": False,
+                "is_error": True,
+            })
+            problems.append(f"Error page detected: {path.name}")
             continue
 
         title = extract_page_identity(page_html)
@@ -244,6 +295,7 @@ for i, path in enumerate(files, 1):
             "redirect": is_redirect,
             "is_category": is_category,
             "is_listing_only": is_listing_only,
+            "is_error": False,
         })
 
     except Exception as e:
@@ -263,7 +315,7 @@ potential_tags = defaultdict(list)
 equivalences = {}
 category_renamed = 0
 category_not_chosen = 0
-
+error_pages = []
 
 def slug_to_title(filename: str) -> str:
     name = Path(filename).stem
@@ -302,7 +354,8 @@ def variant_score(v):
         "_" in filename or
         len(filename) > 40
     )
-
+    if v.get("is_error"):
+        return (True, True, True, True, 0, 9999, "zzz")
     return (
         v["is_listing_only"],
         v["redirect"],
@@ -337,12 +390,25 @@ for article_id, variants in all_variants.items():
                 potential_tags[tag_name].append(normalize_reference_key(v["wg_title"]))
         continue
 
+    if all(v.get("is_error") for v in variants):
+        chosen_variant = variants[0]
+        canonical_pages[article_id] = {
+            "path": chosen_variant["path"],
+            "title": normalize_reference_key(chosen_variant["path"].stem),
+            "redirect": False,
+        }
+        error_pages.append(chosen_variant["path"].name)
+        continue
+
     canonical_pages[article_id] = {
         "path": chosen["path"],
         "title": canonical_slug,
         "redirect": chosen["redirect"],
     }
 
+    if chosen.get("is_error"):
+        error_pages.append(chosen["path"].name)
+
     for v in variants:
         if v["is_category"] and not v["is_listing_only"]:
             # catégorie non choisie
@@ -360,6 +426,7 @@ print(f"{len(canonical_pages)} pages canoniques")
 print(f"{category_not_chosen} pages homonymes 'category_*' non retenues")
 print(f"{category_renamed} pages prefix 'category_*' renommées")
 print(f"{len(potential_tags)} potential_tags enregistrés")
+print(f"{len(error_pages)} error_pages détectées")
 
 # --------------------------------------------------
 # PASS 3 — resolve redirects
@@ -479,6 +546,7 @@ registry = {
     "equivalences": equivalences,
     "potential_tags": potential_tags,
     "ignored_pages": ignored_pages,
+    "error_pages": error_pages,
 }
 
 REGISTRY_PATH.parent.mkdir(exist_ok=True)
@@ -495,6 +563,7 @@ with open(REPORT_PATH, "w", encoding="utf-8") as f:
     f.write(f"Equivalences: {len(equivalences)}\n")
     f.write(f"Ignored: {len(ignored_pages)}\n")
     f.write(f"Problems: {len(problems)}\n\n")
+    f.write(f"Error pages: {len(error_pages)}\n")
     for p in problems:
         f.write(p + "\n")