Error executing a scheduled task running a command cron style in Plesk: Permission denied

Symptoms

• When executing a scheduled task that runs a command to execute a script, it returns a Permission denied error:

  PLESK_ERROR: Task " php -q /var/www/vhosts/example.com/httpdocs/wp-cron.php" completed with error in 0 seconds, output:
  -: php: command not found

  or

  PLESK_ERROR: Task " php -q /var/www/vhosts/example.com/httpdocs/wp-cron.php" completed with error in 0 seconds, output:
  -: /dev/null: Permission denied

• In /var/log/plesk/panel.log, the following entries may be seen with the debug enabled when the task is executed:

  CONFIG_TEXT: DEBUG [util_exec] [64f647aa435003f3d8e65caf25af2807-0] Starting: cron_task_executor -u root -c /var/www/vhosts/example.com/httpdocs/test.sh > /dev/null, stdin:
  DEBUG [util_exec] [64f647aa435003f3d8e65caf25af2807-0] Finished in 0.09011s, Error code: 126, stdout: , stderr: /bin/sh: /path/to/executable/file.sh: Permission denied
  ERR [panel] Task failed: id=726, pid=3245, type=scheduler-run-task, error=Scheduled task failed
  DEBUG [panel] PleskUserException: Scheduled task failed
  file: /usr/local/psa/admin/plib/Scheduler/RunTask.php

• The script /path/to/executable/file.sh executed by the task, does not have permissions to be executed:

  # ls -las /var/www/vhosts/example.com/httpdocs/test.sh
  4 -rw-r--r-- 1 root root 1836 Mar 6 23:30 /var/www/vhosts/example.com/httpdocs/test.sh

Cause

Lack of permissions on the script file or missing command in the chroot environment.

Resolution

1. Log into Plesk.

2. Find the affected file in Domains > example.com > File Manager and add executable permissions:
   

For the .php scripts:

1. Log into Plesk.
2. Recreate the task as Run a PHP script one in Domains > example.com > Scheduled Tasks > Add Task: