When we find that suddenly one day to enter administrator prestashop gives us a glimpse blank and not let us do anything else it may be a space problem . The first thing to do is check whether we are giving an error . To do this we modify the defines.inc.php file and change the line:
define(‘_ PS_MODE_DEV_’, true);
Screen update prestashop manager and we see if it gives some errror . In our case:
Prestashop tools/Smarty/sysplugins/smarty_internal_write_file.php on line 44
If despite clean smarty cache continues the same mistake, it can be a problem of disk space. We free disk space and try to reload the page board administrator and problem solved.