How to implement this subdirectory mapping in multisite?

Not tested…but should work. In your .htaccess file:

RewriteEngine On
RewriteCond %{HTTP_HOST} ^(www.)?mysite.com$
RewriteRule ^(/)?$ us [L]

(and yes…make a copy of your original .htaccess before you muck with it!)

Hata!: SQLSTATE[HY000] [1045] Access denied for user 'divattrend_liink'@'localhost' (using password: YES)