At Muzeek, we use one of the most popular technology partners to send/receive emails: Postmark
Trusted by thousands of companies globally, Postmark ensures accurate and guaranteed delivery of emails via their API, at scale. Companies like Muzeek use Postmark for a delightful email experience that's embedded within our software.
At times however, emails sent through Muzeek (via Postmark's API) may not reach their intended recipients due to what's called "ISP blocks." Usually this is an inadvertent setting where the recipients email client is overly strict about what IPs or domains can send them emails. This article guides you through resolving such issues.
On our Enterprise Plan, you can use your own domain to send your Muzeek emails, which is a fantastic choice to help avoid one of these restrictions. However, certain email clients may still restrict IP addresses they're unfamiliar with, which means even your own domain's emails could be blocked.
Understanding ISP Blocks: ISP blocks occur when emails are rejected by the recipient's mail server, often due to their local policies or, rarely, due to IP reputation issues.
Steps to Resolve ISP Blocks:
Ask to whitelist: Ask the recipient to contact their IT or mail administration team. They should whitelist your sending domain or Postmark’s IP addresses in their mail filter settings. Share the full bounce error message with them for clarity.
Your domain is everything after the "@" symbol for your email. For example: [email protected]
Additionally, send them the following link which gives them the IP addresses they should whitelist: https://postmarkapp.com/support/article/800-ips-for-firewalls
Follow-Up: Once the recipient's organization adjusts its policies to allow your emails, you can resend the messages.
If their changes have been propagated correctly, they should immediately begin receiving emails from you again.
For more detailed information and guidance, please reach out to our Muzeek Support team and we'll offer assistance: [email protected]