diff --git a/core/class/declarationtva.class.php b/core/class/declarationtva.class.php
index 4ef352f..5fdfae2 100644
--- a/core/class/declarationtva.class.php
+++ b/core/class/declarationtva.class.php
@@ -999,6 +999,7 @@ class DeclarationTVA
      */
     public function validateDeclaration($declaration_id)
     {
+        // First, try to update the declaration status
         $sql = "UPDATE " . MAIN_DB_PREFIX . "declarationtva_declarations 
                 SET status = 'validated', 
                     validated_date = NOW(),
@@ -1007,12 +1008,18 @@ class DeclarationTVA
                 AND entity = " . $this->entity;
         
         $result = $this->db->query($sql);
-        if ($result) {
-            return true;
-        } else {
-            $this->error = $this->db->lasterror();
+        if (!$result) {
+            $this->error = "Database error updating declaration: " . $this->db->lasterror();
             return false;
         }
+        
+        // Check if the update actually affected any rows
+        if ($this->db->affected_rows($result) == 0) {
+            $this->error = "No declaration found with ID " . $declaration_id . " or insufficient permissions";
+            return false;
+        }
+        
+        return true;
     }
     
     /**
@@ -1026,18 +1033,26 @@ class DeclarationTVA
     {
         global $conf, $user;
         
-        // Create documents directory if it doesn't exist
-        $doc_dir = DOL_DATA_ROOT . '/declarationtva/validated/';
-        if (!is_dir($doc_dir)) {
-            dol_mkdir($doc_dir);
-        }
-        
-        // Generate filename
-        $filename = 'CA3_Validated_' . $this->declaration_number . '_' . date('Y-m-d') . '.pdf';
-        $dest_path = $doc_dir . $filename;
-        
-        // Copy PDF to documents directory
-        if (copy($pdf_path, $dest_path)) {
+        try {
+            // Create documents directory if it doesn't exist
+            $doc_dir = DOL_DATA_ROOT . '/declarationtva/validated/';
+            if (!is_dir($doc_dir)) {
+                if (!dol_mkdir($doc_dir)) {
+                    $this->error = "Failed to create documents directory: " . $doc_dir;
+                    return false;
+                }
+            }
+            
+            // Generate filename
+            $filename = 'CA3_Validated_' . $this->declaration_number . '_' . date('Y-m-d') . '.pdf';
+            $dest_path = $doc_dir . $filename;
+            
+            // Copy PDF to documents directory
+            if (!copy($pdf_path, $dest_path)) {
+                $this->error = "Failed to copy PDF to documents directory";
+                return false;
+            }
+            
             // Add document record to Dolibarr
             require_once DOL_DOCUMENT_ROOT . '/core/class/ecmfiles.class.php';
             $ecmfile = new EcmFiles($this->db);
@@ -1057,13 +1072,21 @@ class DeclarationTVA
             
             $result = $ecmfile->create($user);
             if ($result > 0) {
-                // Link document to declaration
-                $this->linkDocumentToDeclaration($declaration_id, $ecmfile->id);
+                // Try to link document to declaration (this might fail if table doesn't exist)
+                $link_result = $this->linkDocumentToDeclaration($declaration_id, $ecmfile->id);
+                if (!$link_result) {
+                    // Log the error but don't fail the whole process
+                    error_log("DeclarationTVA: Failed to link document to declaration: " . $this->error);
+                }
                 return true;
+            } else {
+                $this->error = "Failed to create ECM file record: " . $ecmfile->error;
+                return false;
             }
+        } catch (Exception $e) {
+            $this->error = "Exception in saveValidatedPDF: " . $e->getMessage();
+            return false;
         }
-        
-        return false;
     }
     
     /**
@@ -1075,11 +1098,26 @@ class DeclarationTVA
      */
     private function linkDocumentToDeclaration($declaration_id, $document_id)
     {
-        $sql = "INSERT INTO " . MAIN_DB_PREFIX . "declarationtva_documents 
-                (declaration_id, document_id, created_date) 
-                VALUES (" . (int)$declaration_id . ", " . (int)$document_id . ", NOW())";
+        // First check if the table exists
+        $sql_check = "SHOW TABLES LIKE '" . MAIN_DB_PREFIX . "declarationtva_documents'";
+        $result_check = $this->db->query($sql_check);
         
-        return $this->db->query($sql);
+        if (!$result_check || $this->db->num_rows($result_check) == 0) {
+            $this->error = "Documents table does not exist. Please run the database migration.";
+            return false;
+        }
+        
+        $sql = "INSERT INTO " . MAIN_DB_PREFIX . "declarationtva_documents 
+                (declaration_id, document_id, created_date, entity) 
+                VALUES (" . (int)$declaration_id . ", " . (int)$document_id . ", NOW(), " . $this->entity . ")";
+        
+        $result = $this->db->query($sql);
+        if (!$result) {
+            $this->error = "Database error linking document: " . $this->db->lasterror();
+            return false;
+        }
+        
+        return true;
     }
     
     /**
@@ -1090,6 +1128,15 @@ class DeclarationTVA
      */
     public function hasValidatedDocument($declaration_id)
     {
+        // First check if the table exists
+        $sql_check = "SHOW TABLES LIKE '" . MAIN_DB_PREFIX . "declarationtva_documents'";
+        $result_check = $this->db->query($sql_check);
+        
+        if (!$result_check || $this->db->num_rows($result_check) == 0) {
+            // Table doesn't exist, so no documents
+            return false;
+        }
+        
         $sql = "SELECT COUNT(*) as count 
                 FROM " . MAIN_DB_PREFIX . "declarationtva_documents dd
                 INNER JOIN " . MAIN_DB_PREFIX . "ecm_files ef ON dd.document_id = ef.rowid
diff --git a/declarationtva_view.php b/declarationtva_view.php
index cbaf062..5504541 100644
--- a/declarationtva_view.php
+++ b/declarationtva_view.php
@@ -110,10 +110,15 @@ if ($action == 'validate' && $token) {
         $pdf_path = $pdf_generator->generateDetailedCA3PDF($id);
         if ($pdf_path && file_exists($pdf_path)) {
             // Save PDF to Dolibarr documents
-            $declarationtva->saveValidatedPDF($id, $pdf_path);
+            $save_result = $declarationtva->saveValidatedPDF($id, $pdf_path);
+            if (!$save_result) {
+                setEventMessages("Warning: Declaration validated but PDF save failed: " . $declarationtva->error, null, 'warnings');
+            }
+        } else {
+            setEventMessages("Warning: Declaration validated but PDF generation failed: " . $pdf_generator->error, null, 'warnings');
         }
     } else {
-        setEventMessages($langs->trans("ErrorValidatingDeclaration"), null, 'errors');
+        setEventMessages($langs->trans("ErrorValidatingDeclaration") . ": " . $declarationtva->error, null, 'errors');
     }
 }