rename plugins directory not working

Tried renaming plugins to another simple string like wpplugs using the control panel file manager. Added the defines to the wp-config.php in my /home/user/websitename directory just after the <?php line. Double checked that all the paths matched and were type properly, but when load the page, I get a blank page – same with the admin dashboard. I commented out the changes in wp-config.php and renamed the plugins folder back and it works again…