So you want to manually upgrade your WordPress installation since the one-click update option is not available due to an ancient (pre 2.7) version or missing file permissions. Although using the one-click update option is the most comfortable one you can almost as easily update WordPress manually. The following steps show you how to manually update WordPress.
As usual make a backup of your database and your files. In case you don’t have access to tools such as phpMyAdmin or a shell terminal with proper permissions to export your database have a look at Shuttle-Export, which is an easy to use PHP based MySQL dump library. Make sure to remove this tool after the upgrade process again or protect it with .htpasswd since you most likely don’t want strangers to export your database.
Next, before removing files from your existing installation make sure to deactivate all plugins.
Remove existing installation files
Once again, make sure you have backed up your data and deactivated your plugins. Then remove all files and folders except the following from your installation:
Copy new files
Afterwards, copy all files and folders from your new WordPress version, thus overwriting existing files except the ones mentioned above.
Now it’s time to check if a database upgrade is necessary. Thus, navigate to /wp-admin/. If your are asked click on the upgrade database button. Once this is done click continue and re-login into the dashboard as admin.
Finally, check your settings and enable your plugins again. Also check for possible plugin updates. This is all there is to manually updating WordPress. Almost as easy as the one-click update, right? Make sure to remove or password protect your Shuttle-Export installation. You’re all set!