Why can't I open my segmentation rules after the system update?
When your system updates to versions 8.2 and later, the old Simple Segmentation Rule feature is replaced by the new Standard Segmentation Rule implementation.
Simple Segmentation Rules created before version 8.1 still work with campaign deployment and subscriber export as written. The old Simple rules are also available to edit in the new Standard Rule user interface. Any Simple rule that is edited and saved in the new Standard interface is updated to a Standard rule type.
If the Standard Rule editor cannot open a Simple segmentation rule for any reason, an error occurs and the rule will not open for editing; however, it is still usable to send a campaign or export subscribers. This should not be very common, but there are some cases where a condition was defined mixing Field Type and Operator, and this is no longer supported. This will mostly be noticeable if someone has a rule using Zip field and the greater/less than operators, because Zip is a text field and these operators should only work with numbers/float fields.