diff -r a2ce49dfb9fd party.py
--- a/trytond/trytond/modules/party/party.py	Mon May 06 15:04:56 2019 +0200
+++ b/trytond/trytond/modules/party/party.py	Sun Jun 23 15:53:05 2019 +0200
@@ -458,8 +345,11 @@
                     continue
                 for type in Party.tax_identifier_types():
                     module = get_cc_module(*type.split('_', 1))
-                    if module.is_valid(code):
-                        break
+                    try:
+                        if module and module.is_valid(code):
+                            break
+                    except:
+                        pass
                 else:
                     type = None
                 identifiers.append(