My company is using Microsoft Exchange 2010 SP1, there we have a few mailboxes that have permanent out of office assistant set for the purpose of informing people that their message has been received and that we’ll process it ASAP. And that’s fulfilling its purpose, but at some point we realized that the notification is sent only once to each email sender. It doesn’t matter how much time has passed between two sent emails, you would always get out of office reply only for the first message.
This is actually all by design, hard-coded, without the possibility to change or modify this behavior. The Microsoft’s intended purpose for OOF is to notify senders that the recipient is out of office, usually on vacation for some period of time. For that objective, usually there is no need for auto reply with OOF info to be sent out more than once. But for our intents and purposes, this will not do. Those accounts have permanent Auto Reply, and we want our server to respond more than once.
But not too often 🙂 Microsoft left out the possibility to modify OOF settings out of the box for a good reason. If an email server would respond with OOF each time it received an email on that particular mailbox, it could be really easy to either purposely or not cause an email loop. Two mail servers would bounce (auto reply) emails until one of them dies or reaches the mailbox limit. Hence, you should be really careful when meddling with OOF auto reply.
One way I found to make OOF respond more than once is to reset the Auto Reply configuration. Basically, disable it, and enable it right away. The OOF will be sent to each sender again on the first email, at least until the configuration is changed again.
So, one would schedule a PowerShell script to disable/enable OOF on speciefic mailboxes that fit aforementioned intent. Do not reset OOF too often, set the scheduler for an interval of one day at least.
set-MailboxAutoReplyConfiguration -id user.name -AutoReplyState Disabled set-MailboxAutoReplyConfiguration -id user.name -AutoReplyState Enabled