Do you still have the install folder with dolphin? If so go to your phpadmin and drop all tables to your dolphin data base. Then go to http://yoursite/where dolphin is/install/
if you changed the install folder after install like it said to,just go back and change to install. This will reinstall your dolphin and no need to change database name,just "must" drop all tables in dolphin database in your cpanel or hosting admin section. This should help. I have seen this happen to me when i see more replaced folders after changing permisson to the header.php file. It's a quick and easy fix if you have no members yet. Hope this helps.