One of the main issues is that cli access via Drush isn’t an option in a shared server hosting environment. And a lot of issues happen because you may need to flush caches without logging in. So here’s the plan of action:

1. Login to site admin.
2. Clear your caches.
3. Use the backup and restore module to create a compressed sql dump of your db. Make sure that tables with the name “cache” aren’t selected for backup.
4. Open the sql backup file and use a text editor to replace all instances of <dev sitename> with <new sitename> and save.
5. Move all your files to the new server (tarball and extract if possible). Ensure that all hidden .htacess files are also moved across.
6. Fix permissions issues: core files should be chmod 644, all writable directories should be set to 777 and their content set to 755.  If any files in these directories are created by the web user and are subject to change via the CMS, ensure these files are chmod 777.
7. Ensure that the temp directory and files directory are writable.
8. Check that your new setup has the correct sitename for it’s multisite folder and that the database details in the settings file is correct for the new host.
9. Restore the database via phpmyadmin / remote sql client etc.
10. Surf to your new domain – it should show the offline page if you set it to offline and your database settings are correct.
11. Go to the admin page (/admin). If that fails, go to /user to login. If you can’t login, there’s probably an issue with your server setup or site config above.
12. Once you’ve logged in as admin, go to /admin/settings/file-system to check if your file and temp upload directories are setup correctly.
13. Check to see if your site is now loading properly.
14. If your images are broken, it could be imagecache – go to your imagecache setup in the admin section and flush all imagecache items.
15. Flush all site caches.
16. I had some issues with css and js_injector modules as well and ended up having to delete the files it generated in the <files> directory and had to recreate all the rules.

That’s all I can think of for now. Hopefully Drupal 7 can sort out some of this somewhat.

I thought I’d just summarise it to make it easier:

1. Download the Drupal drush package and put it somewhere in your system. Place it utside of the Drupal installation so that there’s no risk of it being executed from the browser.
2. Download the following packages from the sourceforge GnuWin32 project:
   1. Get the latest wget installer here.
   2. Get the latest bzip2 installer here.
   3. Get the latest tar installer here.
3. Install all of the above gnu packages.
4. Set your environment variables to detect all of the necessary binaries:
   1. Go to Start>Run and type sysdm.cpl to bring up the system properties dialog.
   2. Click on the Environment Variables button.
   3. In the System Variables panel, edit the Path variable value:
      1. <existing path>;<path to php>;<path to gnuwin>;<path to drush>;
      2. If you’re on a 64-bit system, gnuwin be in your Program Files (x86) directory.
      3. You can check that each of the above paths are resolving by typing php/tar/gzip/wget/drush in a dos prompt.
5. Start>run>cmd and navigate to your Drupal installation
6. Type drush for a list of commands. Append your commands with -d for debugging if the commands aren’t working.

Hope that helps somebody.