How to correct 500 interval server error??

Question

Hello everyone! I have just rent a hosting and domain to upload my website on internet.And when i upload my website on server it have a 500 interval error and i don't know how to correct it. I use Framework 4.0 .Someone know it please help me to correct it right!!
Note:When i create a project(New project->Asp.Net website application) and then i publish my project and upload it on my hosting .It's work fine.
Please help me.Thanks!