The following message can occur when you try to add a Physical Hosting to a domain in Plesk: “Error: Unable to update hosting preferences: system user update is failed: Unable to create system user: Empty error message from utility.".
Unable to create system user: Empty error message from utility.
Here’s the fix.
In the log file “/usr/local/psa/admin/logs/httpsd_error_log” you’ll see the following entry: /usr/share/cracklib/pw_dict: error reading header.
This can be fixed by doing:
rpm -e cracklib-dicts --nodeps yum install cracklib-dicts