Important: Before updating Manually, Make a Full Backup. A full backup should be taken of both the iBilling files and the database.
Begin by making sure your server meets the system requirements for new version. Current version of iBilling requires- PHP 7.1.3+ MySQL 5.7+ Mbstring PHP Extension PDO PHP Extension GD JSON
Download the latest version from codecanyon or from client portal.
Extract the files then replace all files in the server. It's more easier if you upload the zip copy of files and extract directly in the server. For example in cPanel you can do this. Or if you are using vps, you can use unzip command in the terminal.
After doing this, just login normally & you will be redirected to an update page where it will update the database schema if needed.
Your update is now complete.
How it works?
The zip file does not comes with the config file where your database info and application url is stored. It's only created after first install. So when replacing, your config file will not be replaced. When you first login after replacing the files, it will check the version number in database and version number in files & will redirect to you in update page.