Error: No response from server!

There are so many reasons that the session functionality can be inoperable and they are all different on every host. There is no way I can tell you for sure what is wrong unless I have full access to your servers. If it really doesn’t work on any of your site across multiple servers than it must be something consistant about the platforms you are using. It could also be something wrong with your rewrite rules or something blocking or overriding my .htaccess files. Your server administrators or hosting provider’s tech support should be able to help you troubleshoot session functionality and mod_rewrite. They may know off-hand why it’s not working but if not ask them to check the permissions and free space in the /tmp/ directory, check setting in the php.ini files, look for any .htaccess directives that might be a problem, and view the error_log files to see why the session_start is not working.