Manually Update WordPress Website

1. Download latest WordPress zip (or tar.gz) file.
2. Unpack downloaded zip files.
3. Deactivate plugins.
4. Delete the old wp-includes and wp-admin directories on your web host (through your FTP or shell access).
5. Using FTP or our shell access, upload the new wp-includes and wp-admin directories to your web host, in place of the previously deleted directories.
6. Upload the individual files from the new wp-content folder to our existing wp-content folder, overwriting existing files. Do NOT delete your existing wp-content folder. We should NOT delete any files or folders in our existing wp-content directory (except for the one being overwritten by new files).
7. Upload all new loose files from the root directory of the new version to our existing wordpress root directory.

WARNING - We should replace all the old WordPress files with the new ones in the wp-includes and wp-admin directories and sub-directories, and in the root directory (index.php, wp-login.php and so on). Our wp-config.php will be safe.

We should be careful when we come to copy the wp-content directory. We should make sure that we only copy the files from inside this directory, rather than replacing our entire wp-content directory. This is where our themes and plugins live, so we will want to keep them. If we have customized the default or classic themes without renaming them, make sure not to overwrite those files, otherwise you will lose your changes.

Lastly we should take a look at the wp-config-sample.php file, to see if any new settings have been introduced that we might want to add to our own wp-config.php.