Ping or Sync ActiveSync commands sent to Plesk server with Premium Email fail with error 500

Symptoms

• The extension Plesk Premium Email is installed on the server.

• The account john.doe@example.com is correctly added to Outlook using ActiveSync.

• From the log file /var/www/vhosts/system/example.com/logs/proxy_access_ssl_log​, it is found that Ping or Sync operations fail with the error 500:

  CONFIG_TEXT: POST /Microsoft-Server-ActiveSync?Cmd=Ping&User=john.doe@example.com&DeviceId=74FB9B6F18E744F3BF338506F4311AE6&DeviceType=WindowsOutlook15 HTTP/1.1" 500 601 "-" "Outlook/16.0 (16.0.11231.20120; x64)

• At the same time, the following error is logged in /var/log/roundcubemail/errors.log:

  CONFIG_TEXT: PHP Warning: file_put_contents(/var/log/roundcubemail/console.log): failed to open stream: Permission denied in /usr/share/roundcubemail/program/lib/Roundcube/rcube.php on line 1289

• The ownership for the file /var/log/roundcubemail/console.log is set as follows:

  # ll /var/log/roundcubemail/console.log
  -rw-r--r-- 1 root root 124 Jan 8 19:19 /var/log/roundcubemail/console.log

Cause

Incorrect ownership is set for the file /var/log/roundcubemail/console.log.

Resolution

1. Connect to the server using SSH.

2. Set the correct ownership for the file /var/log/roundcubemail/console.log:

   # chown roundcube_sysuser:roundcube_sysgroup /var/log/roundcubemail/console.log