diff --git a/product/ERP5OOo/transforms/oood_commandtransform.py b/product/ERP5OOo/transforms/oood_commandtransform.py
index 8c1c108f5a76c66c8459e6211ccb8c889165613d..9a8ecdbc7af2a2f677a858de4718d6025585a05a 100644
--- a/product/ERP5OOo/transforms/oood_commandtransform.py
+++ b/product/ERP5OOo/transforms/oood_commandtransform.py
@@ -2,6 +2,7 @@
 from Products.PortalTransforms.libtransforms.commandtransform import commandtransform
 from Products.PortalTransforms.interfaces import idatastream
 from Products.ERP5Type.Document import newTempOOoDocument
+from Products.ERP5.Document.Document import ConversionError
 from Products.CMFCore.utils import getToolByName
 from Acquisition import aq_base
 from zope.interface import implements
@@ -26,9 +27,6 @@ except ImportError:
 
 CLEAN_RELATIVE_PATH = re.compile('^../')
 
-class TransformError(Exception):
-  pass
-
 class OOoDocumentDataStream:
   """Handle OOoDocument in Portal Transforms"""
   implements(idatastream)
@@ -205,4 +203,4 @@ class OOOdCommandTransform(commandtransform):
         data = self.includeImageList(data)
       return data
     else:
-      raise TransformError
+      raise ConversionError('Format not allowed %s' % format)