Request for Review of High Bounce Rate and Internal SMTP Reputation

Hello,

We have reviewed the exported contact and bounce data before proceeding with a paid email verification service. The results show an unusual pattern that may not be explained only by invalid email addresses:

• 3,373 contacts were marked as bounced.
• 2,975 of these bounced addresses belong to Microsoft domains such as Hotmail, Outlook, Live, and MSN.
• Almost 100% of the Microsoft addresses in the list were rejected.
• 3,093 bounces were recorded on the same date, June 22, 2026.
• 919 of the bounced addresses had previously received emails successfully.
• 139 of the bounced addresses had previously opened our emails.

This concentration suggests that Microsoft may have temporarily blocked or rejected the internal Pabbly SMTP server, sending IP, or domain reputation, rather than all these recipients being invalid.

Before purchasing an email verification plan, please provide us with the detailed SMTP bounce codes and rejection messages for the affected campaign, especially for the Microsoft addresses.

Please also confirm:

1. Whether the internal Pabbly SMTP IP used for our campaign had any Microsoft reputation or blocking issues on June 22, 2026.
2. Whether these contacts were classified as hard bounces or temporary/provider-level rejections.
3. Whether Pabbly can review the campaign logs internally before requiring the deletion of almost 3,000 Microsoft contacts.
4. Whether our sending capacity can be restored for a limited test campaign after we remove unsubscribed contacts, spam complaints, and clearly invalid addresses.

We are willing to clean and verify the list, but we need to ensure that valid contacts are not permanently removed because of a temporary SMTP or sender-reputation problem.

We would appreciate a technical review of the bounce logs and a clear explanation of the rejection codes before we proceed.

Best regards,

Centro de Actualización Académica – CENAC

Hello there,

Thanks for contacting us.

As per your analysis, I've escalated the concern to the Email Compliance Team for reviewing your campaign statistics based on the pointers you have raised. We will get back to you as soon as we hear from the Team. It may take up to 48 hours to get back to you.

Thanks & Regards,

Adeel Akhtar
🌐 Pabbly.com

Hello,

Thank you for reaching out.

Here is the update regarding your account and sending access:

• Send-With-Us Access Restored: Your Pabbly (Send-With-Us) access has been unblocked, and your sending capacity is restored.

• Testing & Campaigns: You can now go ahead, test, and resume sending your email campaigns.

• Contact List: You do not need to delete your valid Microsoft contacts from your list.

Please feel free to run a test campaign and let us know if you need any further assistance!

Hello Max,

Thank you for reaching out.

Under our Sending Reputation Tier system, when sending access is restored after an unblock, accounts are initialized at Tier 1 (10% of total plan capacity)—which corresponds to 1,000 emails per day for a 10,000-subscriber plan. This safeguard is applied automatically to rebuild sending reputation safely.

How Your Daily Limit Increases Automatically

You do not need to submit manual requests to increase your limit. The platform continuously monitors your sending metrics and automatically upgrades your tier:

1. Unique Recipient Threshold: Send to roughly 80% of your current tier's daily limit (around 800 unique contacts at Tier 1).

2. Quality Metrics: Maintain healthy campaign results across your sends:

   • Hard Bounce Rate: Under 0.5%

   • Soft Bounce Rate: Under 2%

   • Spam Complaint Rate: Under 0.1%

Once these conditions are met, the system will automatically upgrade your account through Tier 2 (2,500/day), Tier 3 (5,000/day), and Tier 4 (10,000/day) within a few hours following campaign completion.

Handling Your 6,000 Contact Campaign

Progressive Warm-Up (Recommended): Send a test campaign to a batch of 800–1,000 of your most engaged contacts. Once those metrics pass successfully, the system will upgrade your tier so you can send larger volumes in your next broadcast.

Please let us know if you have any questions as you resume your campaigns!