Strikes me that you've got two things you need to fix.

Your application should be split into a front-end (containing the queries,
forms, reports, macros and modules), linked to a back-end (containing the
tables). Only the back-end should be on the server: each user should have
his/her own copy of the front-end, preferably on their hard drive.

You should never be making changes on a production database: your changes
should be made on a test database (the front-end). Once you know that the
change is successful, replace everyone's front-end. You can use the free
utility Tony Toews has at http://www.granite.ab.ca/access/autofe.htm