Hi friend, Today i am going to explain the step to upgrade your Magento website with 1.7.0.2 to 1.8.0.0(stable) Latest version. Please follow this below steps to done this upgrade fast and easy.

Step 1:

You put your website in to Maintenance Mode. On this step you have to create a “maintenance.flag” in your website root directory. So that will make your website to maintenance for users.

Step 2:

a) Backup your Database using PHPMYADMIN Or SSH. That you can export a SQL file for the full database.
b) Backup your whole website files from root directory. This action you can perform simply if your hosting panel has backup options.

Step 3:

Remove the cache and session from this folder directly by FTP.
“var/cache”, “var/session” these folder must be empty before start the next step.

Step 4:

Now Main upgrade step have to start. in this step you have to download the latest version of Magento 1.8.0.0 from this link. Then upload that with your root directory on your server. That must be replace the exiting folders and files in the same magento folder structure.

Step 5:

After complete the above steps. Remove that “maintenance.flag” file to access the admin and go to this menu System > Index management
There you have to Reindex all the listed items.

Step 6:

Now you can make your website live.

After Upgraded to MAGENTO 1.8.0.0 that will arise one issue on the checkout step.

Go to this file on your theme file below mention

/app/design/frontend/default/YOUR-THEME/template/checkout/onepage/payment.phtml

AND

/app/design/frontend/base/default/template/checkout/onepage/payment.phtml

Line number 36

[sourcecode language=”plain”]
<fieldset>
<?php echo $this->getChildHtml(‘methods’) ?>
</fieldset>
[/sourcecode]

Replace with

[sourcecode language=”plain”]
<fieldset id="checkout-payment-method-load">
<?php echo $this->getChildHtml(‘methods’) ?>
</fieldset>
[/sourcecode]

Thanks! Enjoy..