As June7 suggested, your post is lacking in details we need to start trouble-shooting this for you. What have you done to the database, between it working and not working? Your statement "something/someone goofed something" suggests that this is a multi-user environment, if so, is it divided up into a Front End (with everything except the Tables...and a copy on each user's PC) and a Back End, with the Tables, on a shared drive?
Linq ;0)>
The problem with making anything foolproof...is that fools are so darn ingenious!
All posts/responses based on Access 2003/2007