Well your saying you dont have backups if you did have a gallery before so yes you need to do an install because you have no tables and no application right now. The same error your posting throughout this thread is you can not connect to the database so the information your entering for mysql is incorrect. There really is nothing more you can do than to to verify whether you have a valid photopost database and enter the correct mysql to connect to that database and do an upgrade. If you have no working photopost database then you do an install and reinstall the gallery again with proper mysql information to connect to mysql on the server. You host may need to assist you in determining what you have in databases and what the proper connect strings would be.