diff --git a/app/Database/Migrations/20250521000000_FixImageFilenameSpaces.php b/app/Database/Migrations/20250521000000_FixImageFilenameSpaces.php
new file mode 100644
index 000000000..7f7eb39b2
--- /dev/null
+++ b/app/Database/Migrations/20250521000000_FixImageFilenameSpaces.php
@@ -0,0 +1,65 @@
+<?php
+
+namespace App\Database\Migrations;
+
+use CodeIgniter\Database\Migration;
+
+/**
+ * Migration to sanitize existing image filenames by replacing spaces with underscores
+ * This fixes issue #4372 where thumbnails failed to load for images with spaces in filenames
+ */
+class FixImageFilenameSpaces extends Migration
+{
+    /**
+     * Perform a migration.
+     */
+    public function up(): void
+    {
+        $db = \Config\Database::connect();
+        $builder = $db->table('ospos_items');
+        
+        // Get all items with pic_filename containing spaces
+        $query = $builder->like('pic_filename', ' ', 'both')->get();
+        $items = $query->getResult();
+        
+        foreach ($items as $item) {
+            $old_filename = $item->pic_filename;
+            $ext = pathinfo($old_filename, PATHINFO_EXTENSION);
+            $base_name = pathinfo($old_filename, PATHINFO_FILENAME);
+            
+            // Sanitize the filename by replacing spaces and special characters
+            $sanitized_name = preg_replace('/[^a-zA-Z0-9_\-\.]/', '_', $base_name);
+            $new_filename = $sanitized_name . '.' . $ext;
+            
+            // Rename the file on the filesystem
+            $old_path = FCPATH . 'uploads/item_pics/' . $old_filename;
+            $new_path = FCPATH . 'uploads/item_pics/' . $new_filename;
+            
+            if (file_exists($old_path)) {
+                // Rename the original file
+                if (rename($old_path, $new_path)) {
+                    // Check if thumbnail exists and rename it too
+                    $old_thumb = FCPATH . 'uploads/item_pics/' . $base_name . '_thumb.' . $ext;
+                    $new_thumb = FCPATH . 'uploads/item_pics/' . $sanitized_name . '_thumb.' . $ext;
+                    if (file_exists($old_thumb)) {
+                        rename($old_thumb, $new_thumb);
+                    }
+                    
+                    // Update database record
+                    $builder->where('item_id', $item->item_id)
+                        ->update(['pic_filename' => $new_filename]);
+                }
+            }
+        }
+    }
+
+    /**
+     * Revert a migration.
+     * Note: This migration does not support rollback as the original filenames are lost
+     */
+    public function down(): void
+    {
+        // This migration cannot be safely reversed as the original filenames are lost
+        // after sanitization.
+    }
+}
\ No newline at end of file