Membership and roles issues when transfering to webserver?

Hi All,

 I recently had to go about the task of creating a login page for my site and I stumbled accross this tutorial on the ASP.net site: http://www.asp.net/learn/videos/video-45.aspx 

All went well and I created a login for myself and I found it was a very useful tool but when I transfer it from my dev machine to my webserver, it wont authenticate me - it just says 'Your login attempt was not successful. Please try again.'  I have checked that the framework (3.5) on the server and everything is correct and I am using the correct username and password but I can't see why this is happening?

Am I overlooking something or is this a common issue?

Thanks in advance,

James
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