Unable to add more than 100 email addresses to SpamAssassin Black/White list: Only 100 first unique e-mail addresses will be added

Symptoms

Unable to add more than 100 email addresses to SpamAssassin White/Black List in Tools & Settings > Spam Filter > Black/White list or in Domains > example.com > Mail > Email Addresses > john.doe@example.com > Spam Filter. One of the following messages are shown in Plesk interface:

PLESK_WARN: Warning: Only X first unique e-mail addresses will be added

PLESK_ERROR: Only 100 unique email addresses can be added

PLESK_ERROR: ERR [1] PleskUtilException: spammng failed:
file: /usr/local/psa/admin/plib/Service/Agent.php
line: 228
code: 0

Cause

SpamAssassin limitation does not allow add more then 100 emails.

Resolution

NOTE: Large number of addresses in the SpamAssassin white/black lists may significantly reduce server performance.

1. Connect to the server using SSH;

2. Run the following command to set maximum number of addresses. As an example, the maximum number of 150 mail addresses is given: you may choose appropriate number according to your needs.

   # plesk bin settings --set spamfilter_max_addr_list_length=150