dreamweaver help

I am editing in dreamweaver and when I go to preview my site it looks fine or when I save and close and just view my index page it looks fine. After uploading the page to the web instead of the content <div contentmiddle> being in the center of the page as previewed it's in the left side of the page.

I think I'm missing something small but can't figure it out.

If you think you can help me for a min, I would greatly appropriate it. Please PM me. Thanks again

 

As you want us to assume your markup and css then just validate using validator.

 

I think you have not assigned the margin and padding right or you might have added float:left....
If you have not added the float:left code in there then try adding margin: 0 auto; code...

This should solve the problem... If not then let me know...