I think i might have fixed the issue.
I set TAB Order 1,2,3,4 to the respective field. I then set the validation to "only during data entry" and "empty value"
i can select all other fileds but soon as i try and do anything else then the message box appears
I think this maybe the best way
You can also set a validation that requires that the data in the field be a member of the field's value list. Since a user can type info directly into a field formatted with a drop down list, you may want to set such a validation to keep them from making this mistake.