This information was obtained from:
also spelled out here:
http://drupal.org/upgrade (similar to above)
I wanted to have a tutorial on upgrading on my own blog in case this information ever vanishes, since I rely on it everytime I upgrade.
How to Upgrade Drupal
How to upgrade your Drupal installation to the latest stable version, and keeping your content and customization. You have to be careful with using scripts like “Softaculous” because it will upgrade everything for you, but you tend to lose any customization.
Always have a full backup of your Drupal site. If you mess it up, you will kick yourself for not having a backup copy. Think about all that work you put in… gone. It has happened to all of us at one time or other.
assumptions: Outdated Drupal is installed @ www.yourdomainname.com/drupal
Step 1: Download Latest stable release of Drupal: official Drupal site (either a *.ZIP or *TAR.GZ)
Once the download is complete, you need to upload the new version of Drupal on your website. The safest way to do that is to create a new folder in the public_html directory of your website, e.g. drupal_new, and upload the new version package there. Then you need to extract the archive file through cPanel -> File Manager. Extract it to the same directory
If you don’t have cPanel, or dont know how, you can extract the archive on your computer and upload its contents to your account using your favorite FTP client. I personally use FileZilla. It is free and works great. Basically when all said & done, the contents from the zip file should be on your webspace : www.yourdomainname.com/drupal_new or whatever the current version number is i.e. www.yourdomainname.com/drupal-7.12
Step 2: Once you have the new version uploaded in the drupal_new folder, you should copy the necessary files and folders from the old version of Drupal to the new one. Here we assume that you already have a full backup of your live Drupal site. Navigate to the backup folder of your Drupal site and copy the .htaccess file, the sites and the files directories and upload them into the drupal_new folder by overwriting any existing files.
**You will also want to copy over any other directories that you may have created to store files/images that doesnt come with a generic installation i.e. www.yourdomainname.com/drupal/other_images***
Now, go to your cPanel -> File manager -> public_html -> drupal_new/sites/default folder and open the settings.php file for editing. Edit the following line:
$update_free_access = FALSE;
and change it to:
$update_free_access = TRUE;
The changes above will allow you to run the update.php script from your browser.
Step 3: The next step is to update the database of your Drupal.
where yourdomainname.com is replaced with your actual domain name. The screen should look similar to the one below.
Click on the Continue button and follow the instructions.
If there are no errors reported, your Drupal application is successfully upgraded.
Due to security reasons you should turn the $update_free_access variable back to false in the settings.php file:
$update_free_access = FALSE;
Open a new window in your browser and point it to the site you have just upgraded. As we performed the upgrade in a test folder drupal_new you should point your browser to: http://yourdomainname.com/drupal_new/
Once you are sure that the upgraded version of the site works properly you can delete or rename the old folder to drupal_old and rename drupal_new to drupal in order to put the new version live.