experiencing a problem creating new products for my shopping cart.

Ex: in Categories / Products - Audio > Aqeedah, there are 3 buttons: back (http://www.assalafi.com/shop.old/admin/categories.php?cPath=2&cID=5%29, new category (http://www.assalafi.com/shop.old/admin/categories.php?cPath=2_5&action=new_category%29, new products (http://www.assalafi.com/shop.old/admin/categories.php%29. The error is occurring when I press the 'new products' button to create products, I receive (http://templates.doteasy.com/ErrorPages/error404/%29. All files, that I know of, have been uploaded to the server, so how can I fix this issue?
Thanks

How do I correct this error that continues to occur, so that I may begin adding products to my shopping cart?

Is this a clean install or an upgrade?

If an upgrade, from what version and how did you upgrade?

What add-ons have you added to your site?

I am receiving a 404 error message when I try to add new products to my shopping cart. When I click on the 'new products' button, it takes me to a 404 error message. How do I correct this error that continues to occur, so that I may begin adding products to my shopping cart? Is there a file that I have not uploaded to the server?

This was a clean install. I've added 4 categories for the products, however, I cannot add any products to them.

There have been no add-ons added to the site.

Try reloading all of the files and directories in:
/admin

It sounds like you have a bad upload of files that is causing this error ...