Why are emails bouncing to Apple domains like icloud.com, me.com, and mac.com?

Email marketer from Email Marketing Forum explains that Apple may implement greylisting, a technique where the server temporarily rejects an email from an unknown sender. This is to verify the email is legitimate, after a delay it is accepted.

Marketer from Email Geeks reports that Apple is indicating the issue is resolved, and they are seeing successful deliveries again.

Marketer from Email Geeks shares a link to Apple's system status page indicating an iCloud outage.

Email marketer from EmailOctopus explains that a poor sender reputation can lead to bounces with any email provider, including Apple. Factors influencing sender reputation include spam complaints, bounce rates, and overall engagement.

Marketer from Email Geeks reports back that Apple Support confirmed it was a temporary fault and advised resending the emails. He explains how he uses SQL to restore subscribers in Sendy.

Email marketer from Gmass explains that blocklists can cause bounces to all email providers including Apple. If your sending IP address or domain appears on a blocklist then this will result in blocked messages.

Email marketer from Quora says that temporary server issues on Apple's end can sometimes cause emails to bounce. These issues are usually resolved quickly, and resending the email later may be successful.

Email marketer from Mailjet explains that bounces to Apple domains can occur if the email address is invalid or no longer exists. This could be due to typos, account closures, or other reasons.

Email marketer from Reddit suggests that Apple may have stricter spam filtering rules than other providers, leading to legitimate emails being mistakenly classified as spam and bouncing. Factors such as email content and sender reputation can trigger these filters.

Marketer from Email Geeks explains they have temporarily suspended delivery to iCloud while Apple resolves the issue and are proactively reversing any suppression list updates caused by the bounces, drawing from lessons learned from a similar Gmail issue.

Email marketer from Postmark says that one reason for bounces to Apple domains can be "user unknown" or "mailbox unavailable" bounce messages. These can indicate that the email address is no longer valid or has been closed.

Email marketer from Stack Overflow shares that one possible reason for bounces could be incorrect domain configuration, such as missing or incorrect SPF records, which can cause Apple's servers to reject emails.

Marketer from Email Geeks shares that they checked client logs and are seeing the exact same bounce issue with Apple domains, and they are not using SES, indicating it's not specific to any SMTP provider.

Expert from Email Geeks refers to a MacRumors forum thread indicating that messages will eventually be delivered. He notes that the bounces were recorded as hard bounces and added to his suppression file.

Expert from Word to the Wise explains that Apple domains are known for having aggressive spam filters and robust security measures which can be a reason for bounces even if best practices are followed. They highlight that focusing on audience engagement and excellent list hygiene will help with deliverability.

Expert from Spamresource answers that the number one reason for bounces is failing authentication checks (SPF, DKIM and DMARC). Making sure email authentication is setup correctly will resolve the majority of bounce related issues.

Documentation from Apple Support explains that one reason for bounces to iCloud, me.com, and mac.com addresses could be the recipient exceeding their iCloud storage limits. When the storage is full, incoming emails will bounce back to the sender.

Documentation from Spamhaus explains that being listed on the Spamhaus blocklist can cause email delivery issues to various domains, including Apple's. If a sending server's IP address is listed, emails may be rejected.

Documentation from DMARC.org explains that if your domain's DMARC policy is set to reject and your emails fail DMARC authentication, Apple's servers may reject them.

Documentation from DKIM.org explains that DomainKeys Identified Mail (DKIM) failures can lead to email rejections. If an email fails DKIM verification, Apple's servers might reject it as a security measure.

Documentation from RFC Editor explains that SMTP server returns a 5xx error code that indicates a permanent failure. These hard bounces can occur for a multitude of reasons on the recipient end.