We have seen this issue several times now if one of our users enables an existing vacation rule (created in the client) in webmail it will go through and send an email to several (if not hundreds/thousands) of people they have corresponded with within the last month or so. These are not new conversations that are coming in. I can't pinpoint exactly how far back it goes. When we get notified we go in and remove the rule in web access and retract at least all of the internal emails that have gone out. Has anyone else seen this issue before? Is there a way to disable enabling rules in webmail till this gets addressed? Seems if they enable the rule in the client it works properly.