I want to move my Zen Cart installation to another host or a different server

1. On your NEW host, create a new MySQL database. Note the username, password, database name, and host name (usually localhost).

2. Go to your NEW host and upload (FTP) a fresh NEW install using the same version files that you built your other site on.... this will make sure that you get the proper settings in your configure.php files...
While installing, allow it to install the demo products, so that you can test and be sure that it's working nicely.
a. Install  (when asked about the database-table-prefix during Database-Setup, use the same prefix that your old store uses)
b. Test it.
c. Make backups of the NEW server's /includes/configure.php and /admin/includes/configure.php files by downloading them (FTP) to your PC.

3. On your OLD host, Make a COMPLETE backup of your DATABASE and STORE.
a. Use either the "Backup MySQL Database" contribution to do the backup of your database, or use phpMyAdmin to export your entire database ... include the "DROP" tables command, and under Data, choose "Complete Inserts" and "Extended Inserts".
Save the SQL file to your PC for later.     Click here for tips on using phpMyAdmin to export database.
b. Download all your old site's files via FTP (or if you have the option, zip them up on the server and download the zip)

4. Now upload your OLD files over the NEW files on the NEW server, WITH TWO EXCEPTIONS: Don't overwrite the /includes/configure.php and /admin/includes/configure.php files on the NEW server.

5. Go back to phpMyAdmin on your NEW server.
a. Select your NEW database (that you installed the NEW Zen Cart into)
b. DROP all the tables. (Check them all and scroll down and on "With Selected..." select DROP. Confirm Yes.
c. Click on the SQL tab across the top (or "Import" on newer phpMyAdmin configurations) and click Browse.
d. Select the SQL file you made in step 3a when you exported your old database, and click Go.

6. Grab the "Fix_Cache_Key" utility to reset your Admin->Sessions->Session Directory key so that it uses the proper folder path for your new server:
http://www.zen-cart.com/index.php?main_page=product_contrib_info&cPath=40_54&products_id=82 

Simply upload the file to your NEW Zen Cart folder and open fix_cache_key.php in your browser. It will give you status messages. Delete fix_cache_key.php when you're finished.

7. You're done. Open your store and admin areas to see it all ready to go!

8. You should review all your email settings in Admin->Configuration->Email Options -- especially any SMTP server/account settings, and of course all your email addresses.