If Outlook displays an error about rule formatting, you likely have a rule that is malformed. The best thing to do is delete and recreate the rule.
Open the rule editor and find a few rules that are mostly blank as these are most often the cause of these errors. After deleting the blank rules (or problematic looking rules) close the editor by clicking OK. If the problem keeps coming back, try deleting all the rules. If after you restart Outlook, you still get the message above try opening your mailbox using the web version of Outlook, and removing rules from that interface.
After deleting the rule, applying the change and clicking OK to close the dialog box, when I open the rule editor again, I see this…
Is there a way to