Permissions on Windows 2000

I have a computer that I am using as a file server with windows 2000. I have (2) computers that have windows XP Home, (1) that has windows 98SE, and (1) that has Windows XP Pro. I have a Linksys (4) port router, and a D-Link switch that connects to a DSL modem for Internet access.

I have put Office 2000 on the server for us to share. Everyone is backing up their files on the server in their own folders.

The problem is no one is able to use the Office 2000 program: We keep getting a permission error. I though I had set up the permissions to allow users.

We have no problem getting into the other files on the server.

Any suggestions?