Start/notes.ini Parameters/MailHoldUndeliverableOnly

MailHoldUndeliverableOnly

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Parameter: MailHoldUndeliverableOnly
Short description: With mail hold active (router paused), only undeliverable mail stays behind in mail.box – deliverable mails continue to flow normally.

Profile

Parameter
MailHoldUndeliverableOnly
Category
Mail / Router
Component
Server
Available since
10.0
Supported versions
10.0, 11.0, 12.0, 14.0, 14.5, 14.5.1
GUI equivalent
Configuration document
Possible values
0 = hold all mails (default), 1 = hold only undeliverable mails

Description

During maintenance / diagnosis windows, admins like to pause the router (tell router pause) to keep mails from ending up in faulty states. By default, this stops all deliveries – even completely harmless internal ones. MailHoldUndeliverableOnly=1 differentiates: routinely deliverable mails continue to flow, only the problematic (undeliverable) ones remain in mail.box for analysis. As a result, mail service stays available for most users while the admin specifically investigates faulty messages.

Example configuration

MailHoldUndeliverableOnly=1

Notes & pitfalls

  • Works in combination with tell router pause / tell router resume.
  • Takes effect after a router restart (tell router quit / load router) or a configuration reload.
  • Pairs with Mail_Hold_Days (retention period) and router failover settings.
  • In cluster setups, align the behavior with MAILCLUSTERFAILOVER to avoid double deliveries.