diff --git a/CHANGELOG.md b/CHANGELOG.md
index b74bc2c..acf3b96 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -9,6 +9,10 @@ Tyto - Littérateur
 
 # CURRENTLY IN DEV !
 
+## [1.9.17]
+- working on 'check' process
+- - dev on checking file used in some post header tags
+
 ## [1.9.16]
 - working on 'check' process
 - - dev: post database values (lots are missing)
diff --git a/src/usr/bin/tyto b/src/usr/bin/tyto
index 348c3ac..daba6a8 100755
--- a/src/usr/bin/tyto
+++ b/src/usr/bin/tyto
@@ -1,6 +1,6 @@
 #!/usr/bin/env python3
-# Version: 1.9.16
-# Updated: 2023-10-03 1696344805
+# Version: 1.9.17
+# Updated: 2023-10-03 1696349064
 # Tyto - Littérateur
 
 # Copyright (C) 2023 Cyrille Louarn <echolib+tyto@a-lec.org>
diff --git a/src/var/lib/tyto/program/__pycache__/check.cpython-311.pyc b/src/var/lib/tyto/program/__pycache__/check.cpython-311.pyc
index 886576d..66025eb 100644
Binary files a/src/var/lib/tyto/program/__pycache__/check.cpython-311.pyc and b/src/var/lib/tyto/program/__pycache__/check.cpython-311.pyc differ
diff --git a/src/var/lib/tyto/program/__pycache__/post.cpython-311.pyc b/src/var/lib/tyto/program/__pycache__/post.cpython-311.pyc
index 8e5f981..4716b55 100644
Binary files a/src/var/lib/tyto/program/__pycache__/post.cpython-311.pyc and b/src/var/lib/tyto/program/__pycache__/post.cpython-311.pyc differ
diff --git a/src/var/lib/tyto/program/check.py b/src/var/lib/tyto/program/check.py
index 9251f9c..39a9597 100644
--- a/src/var/lib/tyto/program/check.py
+++ b/src/var/lib/tyto/program/check.py
@@ -32,7 +32,7 @@
 # file program  : 
 #--------------------------
 
-import sys
+import sys, os
 from dateutil.parser import parse
 
 import args, domain, langs, debug, post, tools
@@ -306,8 +306,10 @@ def ml_tag_values(ln, tag, stats):
      return False
   
   # Check value2 link for some tags (file, image...)
-  if tag in post.value2s_uri():
-    if not is_value2_file_exists(ln+2, tag)
+  if tag in post.value2s_uri \
+     and not value2.startswith(post.value2s_ext_uris):
+     if not is_value2_file_exists(ln+2, tag, value2):
+        return False
   
   # Convert values to HTML (put in post database)
   html_value = '<a href="%s" class="%s" target="%s" alt="%s">%s</a>'%(
@@ -334,18 +336,39 @@ def ml_tag_values(ln, tag, stats):
 
 #================================#
 # Check value2 uri for some tags #
+# uri starts with:               #
+# - @... for generic articles/   #
+# - /... for root work directory #
+# - ...  for post directory      #
 #--------------------------------#
-def is_value2_file_exists(ln, tag):
-  # check first char if "@" to check file in generic folders
-  print("post: value2", ln, value2)
+def is_value2_file_exists(ln, tag, value2):
+  # uri "@..." means generic folders
+  if value2[0].startswith("@"):
+     # Set defaut directory for files in /files
+     wrk_df = domain.wrk_files
+    
+     # Set directory for images in /images
+     if tag == post.ml_tags[1]: # image:
+        wrk_df = domain.wrk_images
   
-  # Set defaut directory for files in /files
-  wrk_df = domain.wrk_file
-  
-  # Set directory for images in /images
-  if tag == post.ml_tags[1]: # image:
-     wrk_df = domain.wrk_images
+     value2 = value2[1:]
+
+  # uri "/..." means from wrk root folder
+  elif value2[0].startswith("/"):
+       wrk_df = domain.wrk_articles
+       value2 = value2[1:]
   
+  # uri "..." means from legacy post folder
+  else:
+    wrk_df = os.path.dirname(post.uri) + "/"
+       
+  # Check if file exists
+  file_uri = wrk_df + value2
+  if not os.path.exists(file_uri):
+     post.error = \
+     debug.out(5, "%s) %s"%(ln, tag), file_uri, True, 2, False)
+     return False
+        
   return True
 
 
@@ -474,12 +497,10 @@ def titles():
 
     # Count Tyto Comments
     elif line.startswith("#"):
-      print("?? tyto_coms", line)
       post.stats_tyto_text_coms += 1
     
     # Count HTML comments
     elif line.startswith(post.text_comments):
-      print("?? html_coms", line)
       post.stats_html_coms += 1
 
   return True
diff --git a/src/var/lib/tyto/program/post.py b/src/var/lib/tyto/program/post.py
index d03ffd0..5a8aced 100644
--- a/src/var/lib/tyto/program/post.py
+++ b/src/var/lib/tyto/program/post.py
@@ -181,6 +181,7 @@ ml_marks = {
 
 # Markers with uri in value2
 value2s_uri = (ml_tags[1], ml_tags[2], ml_tags[3])
+value2s_ext_uris = ("http", "ftp")
 
 # text_contents
 # =============