PHP Fatal error: Uncaught Error: Call to undefined function mysqli_init() in C:\inetpub\wwwroot\osTicket\include\mysqli.php:28
Stack trace:
#0 C:\inetpub\wwwroot\osTicket\bootstrap.php(194): db_connect()
#1 C:\inetpub\wwwroot\osTicket\main.inc.php(28): Bootstrap::connect()
#2 C:\inetpub\wwwroot\osTicket\scp\staff.inc.php(20): require_once('...')
#3 C:\inetpub\wwwroot\osTicket\scp\admin.inc.php(16): require_once('...')
#4 C:\inetpub\wwwroot\osTicket\scp\settings.php(17): require('...')
#5 {main}
thrown in C:\inetpub\wwwroot\osTicket\include\mysqli.php on line 28
how to fix this error?