VERY IMPORTANT! Before doing anything else please DO CONFIRM that removing the installation directory has no effect on your ability to log in to your site. If you can access your site after removing the installation directory DO NOT carry out the procedure below.
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If you are 100% sure that after removing the installation directory you STILL cannot access your site, keep reading.
First, please make sure that you have multiple copies of your backups. Your backup archives are stored by default in the directory administrator/components/com_akeeba/backup. If you have changed that directory you already know where your backups are stored.
Before doing anything else, download these backups with FTP in Binary transfer mode and keep copies of them on your own computer, NAS, USB flash drive etc. We are about to remove your site. Your backups are the only thing preventing a catastrophe.
Then, remove all of your site files. These are the files and folders you typically see in your public_html, htdocs, httpdocs, www or similarly named directory when you connect to your site by FTP.
After removing those files upload the backup archive and kickstart.php, then access the kickstart.php URL to extract the backup archive and start the restoration.
Nicholas K. Dionysopoulos
Lead Developer and Director
🇬🇷Greek: native 🇬🇧English: excellent 🇫🇷French: basic • 🕐 My time zone is Europe / Athens
Please keep in mind my timezone and cultural differences when reading my replies. Thank you!