By A Web Design
Do a complete backup of the current Database / table data prior attempting an Upgrade.
Use phpmyadmin and take a database backup using Export. Save the sql file in a folder on your harddisk.
Create a zip file of all the folders and files in the current Moodle folder. Save this zip file to a folder on your harddisk. This zip file will be use to roll back a failed Moodle update if necessary.
Obtain the latest copy of dotProject from the Internet.
URL: http://download.moodle.org/windows/

Diagram 1
Download the latest copy of the Moodle and place it in a folder like /public_html/moodle
NOTE: This is the folder where the current installed copy of Moodle exists.Move all the folders and files of the current Moodle install to a folder called “moodleold” for example /public_html/moodle/moodleold.
Unzip the latest downloaded Moodle zip file exactly within the folder /public_html/moodle
OR Exactly where the current version of the Moodle install exists.
NOTE: When the zip file is extracted to /public_html/moodle a folder named moodle will be created within /public_html/moodle. All files will be extracted there. Eg: /public_html/moodle/moodle
The extracted files will then have to be moved:
TO
/public_html/moodle
FROM
/public_html/moodle/moodle
Copy the config.php file from /public_html/moodle/moodleold to /public_html/moodle
Delete the zip file after extraction of its content.
Open your Browser and enter the Moodle URL and the screen as shown in diagram 2 will be rendered in the Browser

Diagram 2
Click
to proceed with the Moodle Upgrade, the screen render in your Browser will be as shown in diagram 3.
PHP Issues with Moodle:
Ensure that your version of PHP is 5.3.3 and above. If a lower version of PHP is in use upgrade PHP.
URL: http://windows.php.net/download/#php-5.3-ts-VC6-x86
Choosing a version of PHP?
If you are using PHP with Apache 1 or Apache2 from apache.org you need to use the VC6 versions of PHP
VC6 Versions are compiled with the legacy Visual Studio 6 compiler
Do NOT use VC9 version with apache.org binaries
Once the correct version of PHP is installed, in the php.ini file ensure that the following extensions are unremmed ( The ; at the head of the extension must be deleted ):
extension=php_zip.dll
extension=php_soap.dll
extension=php_intl.dll

Diagram 3
Click
to proceed with the Moodle Upgrade, the screen render in your Browser will be as shown in diagram 4.

Diagram 4
Click
to proceed with the Moodle Upgrade, the screen render in your Browser will be as shown in diagram 5.

Diagram 5
Moodle has been successfully Upgraded.