diff --git a/DeDRM_plugin/__init__.py b/DeDRM_plugin/__init__.py
index 00640d1..c20dd1e 100644
--- a/DeDRM_plugin/__init__.py
+++ b/DeDRM_plugin/__init__.py
@@ -129,6 +129,7 @@ class DeDRM(FileTypePlugin):
     minimum_calibre_version = (1, 0, 0)  # Compiled python libraries cannot be imported in earlier versions.
     file_types              = set(['epub','pdf','pdb','prc','mobi','pobi','azw','azw1','azw3','azw4','azw8','tpz','kfx','kfx-zip'])
     on_import               = True
+    on_preprocess           = True
     priority                = 600