We run batch jobs early each day that send out customers information regarding the status of their orders (confirmation, updates, shipping details etc). This has worked fine until recently, coinciding with a spike in holiday orders.
Now we find that Exchange online is identifying this outbound email as spam, and although we can unblock the sending address this provides only a temporary solution. We believe this issue is primarily tied to the volume being sent over a short period of time. We have contacted MS support on this (and escalated up through the chain) but as may be expected they have offered little by way of solution (their goal is to protect recipients from spam/maintain reputation with downstream ESP's).
We understand that the underlying issue lies in the design of the sending application (batch job sends out high volume with same sender & subject over short period of time) but we are reluctant to an initiate a system redesign at our busiest time of the year.
We are considering relaying this email directly from our system to a service that may be able to better handle this scenario. Is anyone doing this with success today, can advise on a suitable service? Do you have any other suggestions on how we may be able to get this legitimate order status email to our customers?
We understand the best way to prevent email being trapped as spam is to do what we can to prevent is looking like spam, we're just looking for a short term fix at this point.