Help!! Lost all our products

We installed zen-cart onto our (hosted) server a week or so ago, and initially were able to add products. Now, not only can we not add products, but none of the products that were there from the zen-cart demo are there either. When trying to click on a product link, or trying to make a new product, all we get is Error 404 - Page Not Found.

Is this the result of a hack, or is this a problem of out own making?

Initially we didnt have a password set up on the site, but as far as i can remember the problems only started a few days after putting the password on.

Anyone know what the problem is, and maybe the solution too?

Any assitance would be much appreciated

Benjy

oh, and the website is https://www.tech-easy.co.uk, but we havent moved the shop into the main domain yet, and the rest has password protection on it, so you wont be able to see the site yet.

If you do need to see it to help fix the problem then i can take the password off, but otherwise it's preferable to keep it on!