How To Upgrade Wordpress

Before you get started, make sure you meet the minimum requirements.

There is two ways to upgrade wordpress, that is automatic upgrade and manual upgrade.

Recent versions of WordPress feature an Automatic Upgrade. Login to your admin page, You can launch the automatic upgrade by clicking the link in the new version banner (if it’s there) or by going to the Tools -> Upgrade menu. After that it should be straightforward.

Automatic Upgrades do fail sometimes, though, so remember to backup your database first, and deactivate your plugins before starting the upgrade.

Note that your files all need to be owned by the user under which your Apache server executes, or you will receive a dialog box asking for “connection information,” and you will find that no matter what you enter, it won’t work.

If the automatic upgrade doesn’t work for you, don’t panic, just try a manual upgrade.
Manual Upgrade

Step one

Get the latest WordPress. Either download and extract it to your computer or download it directly to the server.
Delete your old wp-includes and wp-admin directories.
Copy the new WordPress files to your server, overwriting old files in the root, except perhaps the wp-content folder (see “NOTE” below). You may use FTP or shell commands to do so. Note that this means *all* the files, including all the files in the root directory as well. If you use the default or classic theme and have customized it, then you can skip that theme.

NOTE The wp-content folder requires special handling, as do the plugins and themes folders. You should copy over the contents of these folders, not the entire folder. In some cases, copying the entire folder may overwrite all your customizations and added content.

Also take care to preserve the content of the wp-config.php file in the root directory. This file contains current settings for your existing installation, e.g. database sign-in information. Occasionally new versions of WordPress add statements to this file. (E.g. in version 2.5 the SECRET_KEY variable was added, see Extended upgrade instructions). Compare your existing file with the new installation file which is named wp-config-sample.php. Either transfer your settings to the sample-file and rename it to wp-config.php or copy the new statements from the sample file into your current file.

Step two

Visit your main WordPress admin page at /wp-admin. You may be asked to login again. If a database upgrade is necessary at this point, WordPress will detect it and give you a link to a URL like http://example.com/wordpress/wp-admin/upgrade.php. Follow that link and follow the instructions. This will update your database to be compatible with the latest code. If you fail to do this step, your blog might look funny.

Now, Your WordPress installation is successfully upgraded.