Forum Discussion
Third party email vendors and DKIM
Our group supports many agencies with in one tenant and with one sending domain. That said there are many outside vendors that send as "ourdomain.com". Is there a limit to the number of DKIM entries ...
andydavid1True but I don't believe SPF is going to check 40 to 50 addresses. I think 10 is the limit.
Michael Wehking 10 DNS lookups. You mitigate that by not doing includes. Instead expand out all the allowed sending IPs and add those to the SPF record instead.