If there is a problem with the user's billing address, still let them get into the Cart. Fixes bug #12081.

docs/changelog/7.x.x.txt

@@ -4,8 +4,8 @@
  - fixed #12084: Greenportal links are sometimes white on white
  - rfe   #618:   Syndicated Content Asset: Make images in the downloaded RSS-feeds available in the template.
  - fixed #12086: Shop Billing Address Unpopulated
- - Snippets can now select a template parser (instead of being restricted to
-   the configured default)
+ - Snippets can now select a template parser (instead of being restricted to the configured default)
+ - fixed #12081: addrees not in addressbook after user change in session
 
 7.10.12
  - fixed #12072: Product, related and accessory assets

lib/WebGUI/Shop/Cart.pm

@@ -1178,6 +1178,9 @@ sub www_view {
             if ( defined $billingAddress ) {
                 $billingAddressOptions{'update_address'} = sprintf $i18n->get('Update %s'), $billingAddress->get('label');
             }
+            elsif (my $e = WebGUI::Error->caught("WebGUI::Error::ObjectNotFound") && $self->get('billingAddressId')) {
+                $self->update({billingAddressId=>''});
+            }
         }
 
         %billingAddressOptions = (%billingAddressOptions, %addressOptions);