Since you tried upgrading Joomla! 2.5 to 3.3 you can't restore your backup just yet – the site would be left in a confused state and fail to load.
First download your backups to your computer. For good measure make three copies of each backup and store them in different media. You can never be too paranoid about having copies of your backups.
Then, remove all files from your live site.
Now upload your backup archive and kickstart.php to your site and do the restoration. This will get your site back.
Next time you try an upgrade from Joomla! 2.5 to 3.x do it like the pros, applying the upgrade locally and then transferring the upgraded site back to your server:
- take a backup of your site
- restore it to your computer. You can use XAMPP, WAMPServer, MAMP or something similar to provide the local server environment.
- perform the update from 2.5 to 3.x on your local server
- take a backup of the now upgraded local site
- remove all files from your live site
- upload the backup archive of the upgraded site and kickstart.php to the live site
- run kickstart.php
Nicholas K. Dionysopoulos
Lead Developer and Director
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