fail one dll in website aspNET

A year ago I got a website in aspx (I believe known for. NET) only now my client realized that the searches do not work. The result file [login to view URL] requires a [login to view URL] file as the name does not exist. Who made ​​me websitew disappeared. The site works with all of the searches exessão: when looking for a Ford Fiesta shows the result of all vehicles on the website. [login to view URL] can remake this? I d'ont have the source code. Framework is 3.5 Acess and More details in contact