ok, leave the control source blank, do not set it to '=Date()'.... better yet... My best advice here is to delete the calendar control and then add a new calendar control in it's place, so that everything is set to it's default (just to make sure nothing was changed)
Once you have the new control made go to the properties of the entire form (make sure the properties box title says FORM. Then goto the EVENT tab on the properties box. It should show a box titled 'On Current' When you select 'On Current" a button with 3 periods (...) should show up. Press that button. Access will then ask you to Choose Builder. Select 'Expression Builder' then press 'OK'.
When the Expression Builder box pops up, type in:
Forms![formname]![controlname].Today
Make sure you change the formname to the name of the form, and controlname to the calendar controls name. (FYI, leave the brakets [] around the names.)