Blank page coming after osclass website upload and configure

I just shift my website http://www.egoota.com from hostgator shared hosting to Linode VPS. After uploading website files and importing database, configured config.php but I'm getting blank home page. for to just check I put the install.php url and it's shows message "Looks like you've already installed OSClass. To reinstall please clear your old database tables first."

That means it's linked to database.

Somebody please help how to get this work, new installation is working but shifting old sites and database not.