How to configure Magento to work with a new domain or change its directory

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In order to configure Magento to work with a new domain or change its current directory, you can follow either of the two solutions:
If you are able to log into Magento's backend, you can easily modify the base URLs of the site via:
System -> Configuration -> Web (Under the General section) -> Unsecure
There change the Field "Base URL" to the new domain.
System -> Configuration -> Web (Under the General section) -> Secure
Here, the "Base URL" field should either match the site's domain or, if you have purchased a Private SSL certificate for the site, here you should type the https form of the URL of your Magento store.
If you do not have access to the backend anymore, you need to modify the URL within the database. Simply open up the database using phpMyAdmin, then navigate to the core_config_data table inside.
Click the Browse tab and edit the first two fields:
    •    web/unsecure/base_url
    •    web/secure/base_url
The last thing you need to do is clear the cache. The Magento cache folder is located in your Magento installation directory > /var/cache. To clear the cache, delete the folder and create it again.