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Reply to All

When this setting is enabled, every email address in the To: and Cc: headers will also be added as a participant on new tickets

By default, only the email address in the From: header is automatically added as a participant. The other addresses are suggested to a worker as potential participants when replying.

Always exclude these addresses as participants

Any email address matching one of these patterns will not be permitted as a participant on tickets.

By default, this list includes any email address beginning with postmaster@ or mailer-daemon@ to prevent auto-responder loops.


Email attachments are enabled by default. If this option is disabled, email attachments will be ignored on incoming mail.

When attachments are enabled, a maximum file size can be configured. This defaults to 10MB.

It's a good idea to send large files as links rather than attachments.

Displaying HTML Messages

When displaying email messages in HTML format, Cerb will use the Tidy1 PHP extension when available to correct common syntax errors.

As part of this process, extraneous markup is cleaned up from mail sent by Microsoft Office applications. In rare situations this can cause issues, and you can disable the functionality here.

Default Ticket Mask Format

Cerb will use this pattern when generating reference masks for new tickets.

By default, the format is LLL-NNNNN-NNN, which provides a mask with three leading letters for quick and efficient lookups. This minimizes the amount of information required from a customer over the phone, etc. Contrast this with masks that begin with the current year, which can have millions of matches with the same first digits.

You can define a different mask pattern here, with the caveat that it must meet a minimum cardinality of 10,000,000 possible combinations. The default mask format has 672,605,015,625 combinations.

The default mask format has 25^3 * 9^8 combinations because the letter O and the number 0 are excluded for their ambiguity.


  1. Tidy PHP Extension -