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What’s New With Port25’s PowerMTA v4.5

PowerMTA from Port25 is an industrial-strength software for high-volume email delivery. Designed for performance, deliverability and manageability, PowerMTA is able to consistently deliver millions of emails per hour. With it’s extensive configuration capabilities and VirtualMTA technology it provides granular control of sources, sending IPs, and domain policies.

Port25 recently introduced PowerMTA v4.5 as a major new release of PowerMTA. It now includes a wide variety of new advanced features and functionalities that allow for greater flexibility and delivery control to help maximize overall performance and deliverability.

PowerMTA Management Console (PMC) v1.5 is also now available with support for all new PowerMTA v4.5 features.  Other new features in the PMC include: IP based reporting, saved reports, configurable session timeouts, and advanced reporting filters including sets and regular expressions.

Key features included in the release:

  • Scheduled Delivery Control – PowerMTA now supports the ability to schedule deliveries via a header. This may be very useful for instances when it takes a long time to build a campaign, or if you need to adhere to strict delivery windows.
  • Precached domains support – To help optimize DNS usage during peak sending times, PowerMTA now offers the ability to precache predefined domain names to ensure the DNS name is always available.
  • IP Rate Limiting – IP rate limiting allows for controlling the number of attempted recipients on a per-hour, per-minute and per-second basis for each IP address for each domain/VirtualMTA. This is primarily used by sites that define multiple IPs in a single VirtualMTA, and that want to limit the attempted delivery rate for each IP address in the VirtualMTA to the respective domains. One can also specify the maximum number of connections to be opened for this domain during the specified time period per IP per domain/vmta.
  • Auto Cold VirtualMTA Rate Increase – PowerMTA now supports the ability to auto-increase cold VirtualMTA mail volumes with a list of daily limits. This makes it very easy to have a set it and forget it configuration for warming new IP addresses.
  • Address Suppression Lists – Addresses in the suppression list are rejected (or turned into bounces, depending on options) during submission. This is very useful for sites that do not have complete control of the list to which they are mailing.

Other Noteworthy Enhancements in PowerMTA v4.5:

  • Custom retry intervals
  • Enhanced job control (pause & resume)
  • Recipient events listing
  • Second DKIM signing support
  • Backoff reason insight
  • Time interval for bounce-upon-no-mx
  • Defer-queue option in SMTP pattern list
  • Disabling of accounting records per queue
  • Domain definitions in virtual-mta-pools
  • Reverse DNS check support on inbound connections
  • TLS information in accounting file fields
  • Pattern matching support on non-ASCII headers
  • Added inbound AUTH username to accounting field
  • Change recipient priority on-the-fly

By Port25, A Message Systems Company

Port25, A Message Systems Company, provides highly focused email delivery software that addresses the ever-expanding needs of client communications and digital messaging apps. Port25’s flagship product, PowerMTA™, has a global footprint, with over 4,000 installations in more than 51 countries.

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