Why am I getting soft bounces from Windstream, TDS, CenturyTel, Hughes and Zoom Internet?
Summary
What email marketers say8Marketer opinions
Email marketer from Mailjet explains that soft bounces occur when the recipient's mailbox is full, the server is down, or the message size is too large. They also state that soft bounces can sometimes indicate temporary deliverability issues.
Email marketer from EmailOnAcid highlights that soft bounces could be caused if your IP address has been listed on a blocklist. Suggesting you use tools such as the MultiRBL tool.
Email marketer from GlockApps highlights that soft bounces could be caused by the content in your emails triggering spam filters. This includes suspicious words, overuse of punctuation, and large images
Email marketer from HubSpot describes soft bounces as temporary delivery failures, noting that the issue might resolve itself. Examples include a full inbox or a temporary server outage.
Email marketer from Reddit suggested checking domain reputation because soft bounces could be because of a poor reputation with those ISPs and their spam filters. They also suggest looking into blacklists.
Email marketer from Stack Overflow shared that soft bounces might indicate the message was flagged as spam and delayed. They mention checking sender reputation and email content.
Email marketer from Litmus highlights that consistent soft bounces could be a sign of inbox placement issues. They suggest monitoring sender reputation, authenticating emails, and reviewing email content for spam triggers.
Email marketer from Sendinblue defines a soft bounce as a temporary issue, such as a full inbox or server problem. They indicate that repeated soft bounces to the same address can eventually turn into a hard bounce.
What the experts say5Expert opinions
Expert from Spamresource explains that soft bounces can be caused by greylisting, where the receiving server temporarily rejects the email to verify the sender's legitimacy.
Expert from Email Geeks identifies that 'VI' likely refers to VADE, a spam filtering service.
Expert from Spamresource suggests that soft bounces can indicate a possible reputation problem. It's worth checking your sending IPs for blocklistings.
Expert from Email Geeks shares a link to Vade's sender tool for checking if you're being blocked: <https://sendertool.vadesecure.com/>
Expert from Word to the Wise, Laura Atkins, explains that snowshoe spamming, where spammers use many IPs with low volumes, can make filtering difficult and potentially lead to delivery issues, which may manifest as soft bounces if your IPs are being affected by spamming from bad neighbors.
What the documentation says2Technical articles
Documentation from AWS Simple Email Service (SES) categorizes bounces as hard or soft. Soft bounces can be due to temporary issues, and SES will attempt to redeliver the email for a period. Continued soft bounces will eventually result in a hard bounce.
Documentation from RFC Editor explains that SMTP enhanced status codes provide detailed information about delivery problems. A 4.X.X code generally indicates a transient failure, which aligns with the definition of a soft bounce.