diff --git a/application/Espo/Modules/Crm/Entities/Document.php b/application/Espo/Modules/Crm/Entities/Document.php
index ea54ab25eb..f6654fecd6 100644
--- a/application/Espo/Modules/Crm/Entities/Document.php
+++ b/application/Espo/Modules/Crm/Entities/Document.php
@@ -47,6 +47,13 @@ class Document extends Entity
         return $this->get('name');
     }
 
+    public function setFile(?Attachment $file): self
+    {
+        $this->relations->set('file', $file);
+
+        return $this;
+    }
+
     public function getFileId(): ?string
     {
         return $this->get('fileId');