The best option is often to look at error logs compiled by your website script, however this isn't always possible. Within cPanel there is limited availability to view Apache/LiteSpeed error logs, to find these:

1. Login to cPanel.
2. Go to the Error Log icon.
3. This will list the last 300 errors.

This may not always list all errors, so if this doesn't turn up any clues you may lodge a Support Request through your Synergy Wholesale System account.