Manual Update
These are the short instructions, if you want more check out the
extended upgrade instructions. If you experience problems with the Three Step Update, you may want to review the
more detailed upgrade instructions
For these instructions, it is assumed that your blog's URL is
http://example.com/wordpress/.
Step 1: Replace WordPress files
1. Get the
latest WordPress zip (or tar.gz) file.
2. Unpack the zip file that you downloaded.
3. Delete the
old wp-includes and
wp-admin directories on your web host (through your FTP or shell access).
4. Using FTP or your shell access, upload the new
wp-includes and
wp-admin directories to your web host, overwriting old files.
5. Upload the individual files from the new
wp-content folder to your existing
wp-content folder, overwriting existing files. Do NOT delete your existing
wp-content folder. Do NOT delete any files or folders in your existing
wp-content directory (except for the one being overwritten by new files).
6. Upload all new loose files from the root directory of the new version to your existing wordpress root directory.
NOTE - you 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 (such as index.php, wp-login.php and so on). Don't worry - your wp-config.php will be safe.
Be careful when you come to copying the wp-content directory. You should make sure that you only copy the files from inside this directory, rather than replacing your entire wp-content directory. This is where your themes and plugins live, so you will want to keep them. If you have customized the default or classic themes without renaming them, make sure not to overwrite those files, otherwise you will lose your changes. (Though you might want to compare them for new features or fixes..)
Lastly you should take a look at the wp-config-sample.php file, to see if any new settings have been introduced that you might want to add to your own wp-config.php.
Step 1.5: Remove .maintenance file
(This step shouldn't be necessary with
www.000webhost.com)
If you're upgrading manually after a failed auto-upgrade, delete the file .maintenance from your WordPress directory using FTP. This will remove the "failed update" nag message.
Step 2: Update your installation
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. You should do this as soon as possible after step 1.
Step 3: Do something nice for yourself
If you have caching enabled, your changes will appear to users more immediately if you clear the cache at this point (and if you don't, you may get confused when you see the old version number in page footers when you check to see if the upgrade worked).
Your WordPress installation is successfully updated. That's as simple as we can make it without
Updating WordPress Using Subversion.
Consider rewarding yourself with a blog post about the update, reading that book or article you've been putting off, or simply sitting back for a few moments and letting the world pass you by.
Step 4: Final Steps
Your update is now complete, so you can go in and enable your Plugins again. If you have issues with logging in, try clearing cookies in your browser.
Troubleshooting
If anything has gone wrong, then the first thing to do is go through all the steps in our
extended upgrade instructions. That page also has information about some of the most common problems we see.
If you experience problems after the upgrade, you can always
restore your backup and replace the files with ones from your previous version from the
release archive.
Source:
Updating WordPress