Can't access sites created in Multisite. Sub Domain set up.

Hi WPMU Dev,

I am attempting to set up my first multisite installation. I am using the sub domain configuration and have wild card sub domains set up.

Problem is, when i create a new site i am unable to visit the dashboard or the front end of the newly created site.

My host has confirmed all *.mydomain.com domains are pointing to the same wordpress directory.

I have checked through many posts on this support and can confirm my .htaccess file is set up correctly, i can also confirm permissions on files and folders are set up correctly.

Is there something not so obvious (or really obvious) i could be missing here.

Many thanks in advance.

Paul