I just ran my list through a list hygiene service to spot any bad emails. I found out that many belong to a domain that has enabled Greylisting.
For those of you that don’t know, “Greylisting is a method of defending e-mail users against spam. A mail transfer agent (MTA) using greylisting will “temporarily reject” any email from a sender it does not recognize. If the mail is legitimate the originating server will try again after a delay, and if sufficient time has elapsed the email will be accepted.” Source
So is A/C compatible with servers that have enabled greylisting? That is, will you re-attempt delivery with a temporary reject? Or simply mark is as a soft bounce and move on.
I’m just trying to make a final decision on these emails since they are impacting Interaction rates.
Great question! The answer is Yes, ActiveCampaign is fully capable of handling temporary rejections/deferrals/greylistings, which are all very similar terms for the same thing. This happens when we try to deliver email to an ISP like Yahoo, and Yahoo says, “we’ve already received enough mail from you in the last few minutes, please wait a few minutes and try again”
We do retry these message many times (often hundreds of times), with a maximum time of 72 hours. We have a very advanced algorithm that knows how often to retry for each ISP, because each ISP has it’s own rules and they don’t want us to bombard them.
Greylisting is mostly used by ISPs to restrict the mail from a sender they don’t completely trust (new sender, sender with high complaints etc). If you have good sending practices with open rates at or above the industry average you should see most greylisting/deferrals largely vanish.