A simple plugin that you can use that will let your clients contact you from right on their dashboard. The email you get from them will include a bunch of diagnostic info that you can use to help get an idea about the problem. This includes: PHP Version Server type (Apache / Ngnix) MySQL version WordPress version Site URL Active plugins Inactive plugins And more! If you have any questions feel free to visit my website http://www.moeloubani.com and ask. Enjoy!