Chockomonkey

I'm posting on behalf of my dad for this one... He owns his own small business. At this place of work, they have a star network set up. On this network, they have an about 5-year-old server running windows 2k server (it is just plugged into the hub like any other computer). The purpose of the server is to host an accounting program that certain people on the network can access, act as a mail server for e-mail throughout the network (they don't have the internet going to all the computers), and as a common storage medium. It has a harddrive that has been set up to allow everyone on the network access without restrictions (i.e. anyone can save, delete, create, view, etc.) here is my question. Not knowing anything about windows 2k server, i have no idea how deleting works. What happened, is someone on the network was (like every other day) using the storage drive on the server, and accidentally deleted quite a few important files. (i don't know if it was a shift-del or not, or if that even matters) My dad went onto the server and looked in the recycle bin, and found nothing. The question is, is there any way that these files could be recovered? As you can guess, they are pretty important. Your time and help would be appreciated... thanks in advance!