Sidebar not visible after changing to new domain

Don’t replace old url to new url in database file.
wp-login.php can be used to (re-)set the URIs. Find this line:

require( dirname(__FILE__) . '/wp-load.php' );

and insert the following lines below:

Do comment/remove these lines. (once the database is updated)

update_option('siteurl', 'http://your.domain.name/' );
update_option('home', 'http://your.domain.name/' );

for more information http://codex.wordpress.org/Moving_WordPress