Blocked Again After Sending 10,000 Verified Emails

Hello Support,

We verified our entire email list using your application before starting our email campaign. We had already verified 50,000 email addresses and confirmed that they were deliverable.

Following your advice, we started sending the emails in batches of 10,000 per day. However, we were blocked again after sending 10,000 emails.

We are only seeing soft bounces and no hard bounces, and all of the email addresses in the batch had already been verified as deliverable.

Could you please help us understand why we are being blocked again despite following your recommended sending limit and using a fully verified email list?

Thank you for your assistance.

Hi,

Thank you for sharing the details.

We checked the sending activity and found that the soft bounce rate exceeded the permitted threshold, which resulted in the sending being blocked.

We also found bounce responses such as: SMTP; 554 5.7.1 [CS01] Message rejected due to local policy.

This indicates that some recipient mail servers rejected the messages due to their local policies. Even though the addresses were previously verified as deliverable, email verification cannot guarantee successful delivery, as recipient-side policies and other delivery factors can change over time.

We are reopening your email sending access. However, please ensure that your email content is relevant and follows email-sending best practices, and monitor the bounce rate closely during future campaigns. If the bounce rate starts increasing, we recommend pausing the campaign and reviewing the affected recipients before continuing.

Please take care to avoid repeated high bounce rates, as this may result in sending restrictions again.

May I kindly ask for an update on when we can expect our sending back to be processed? I have already raised my concern in another thread.

Thank you for your assistance, and I look forward to your update.

Hi Team,

Please note that we have unblocked your Pabbly sending with us. However, we would request you to clean your subscriber list wherever possible.

We would also suggest avoiding sending emails to iCloud/Mac.com and Yahoo domains for now, as these domains are generating a significant number of soft bounces.

We will also investigate this from our end to understand the issue further and check if there is anything we can do to improve the delivery.

Thank you for your cooperation and understanding.

Hi Team,

Our technical team found that the issue is related to the quality of your subscriber list. The list had approximately 4% hard bounces, along with a significant number of inactive or disabled mailboxes.

We also found that Apple temporarily blocked your sender domain based on the sending activity from your campaigns. This is not related to our shared IPs, as other customers using the same IPs continue to deliver successfully to Apple.

To prevent the issue from occurring again, we recommend the following:

• Clean your subscriber list and remove inactive, invalid, or previously bounced email addresses wherever possible.

• Avoid sending emails to Apple domains, such as iCloud and Mac.com, for the next 1–2 weeks.

• During this period, send only to your cleaner and more engaged subscriber segments.

• When you resume sending to Apple domains, start with small batches and closely monitor the bounce rate.

• If the bounce rate starts increasing again, pause the campaign and review the affected recipients before continuing.

At this point, no further action is required from our end. The key next step is to clean your subscriber list and temporarily avoid Apple domains before gradually resuming your sending activity.

We understand that you had already verified your list. However, based on our technical investigation, improving the list quality and gradually rebuilding your sending reputation will help prevent similar restrictions in the future.

Hi Team,

We’re following up on the email delivery issue discussed earlier.

As shared, the technical team found that the issue is related to the quality of the subscriber list and the temporary restriction from Apple. The recommended steps were to clean the list, temporarily avoid Apple domains, and gradually resume sending with smaller batches.

Please let us know if you need any further assistance regarding this issue.

Hi Team,

We’re following up on our previous email regarding your query. As we haven’t received a response, this will be our last follow-up, and the ticket will be closed automatically.

If you still need assistance, you can email us again at support@pabbly.com to raise your concern.

Thanks & Regards,
Vinay Jain
Customer Support Associate
🌐 Pabbly.com

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