I have created a single user db having the tabes "Department", "Subjects", "Option" among others.

I have created a query using fields from the three above mentioned tables whose relationships are well defined. Then i have used this query to create a report. Initially it was funtional, later on when i try to open the report, i get the massage "The database cannot lock the table Department because it is already in use by another person or process".

I am fraustrated, i dont know what to do. I NEED YOUR HELP: