Change format of a date field to use as part of a file name.

Good afternoon!

I am using Livecycle ES3 and Adobe Professional XI

I have a livecycle form for employee evaluations.

I am saving a file based on field names.  My problem is when I use a date field as part of my file name.  I have the scripts working for the trusted function and for the button field on the form.  They are listed below.

Folder level script--

mySaveAs = app.trustPropagatorFunction(function(doc, path)
{
     app.beginPriv();
         doc.saveAs(path);
     app.endPriv();
});

myTrustedSpecialTaskFunc = app.trustedFunction(function(doc, file_path)
{
     // Privileged and/or non-privileged code above
     app.beginPriv();
          mySaveAs(doc, file_path);
     app.endPriv();
});

Button script

myTrustedSpecialTaskFunc(

this, "/c/myfiles/" + ReviewPeriodTo.rawValue+ "-" + Div.rawValue + "-" + EVALTTYPE.rawValue + "-" + LASTNAME.rawValue + "-" + FIRSTNAME.rawValue +

".pdf");

My problem is the ReviewPeriodTo.rawValue.  When I enter the data into the form and don't enter a value for ReviewPeriodTo field, the file is saved with the values from the other fields, and a null is inserted where the date field would go.

When I type in a value such as 2014-03-15 in the ReviewPeriodTo field along with values in the other fields, it works.

When I try to put a value in such as 3/15/2014 in the ReviewPeriodTo field, I receive the following error.

RaiseError: The file may be read-only, or another user may have it open. Please save the document with a different name or in a different folder.

Doc.saveAs:16:XFA:form1[0]:Page1[0]:#subform[0]:Button3[0]:mouseUp

===> The file may be read-only, or another user may have it open. Please save the document with a different name or in a different folder.

My problem is, this is part of a much larger process where I am importing the information from a make table query from MS Access that is exported to Excel.  If I could just format the field data automatically to the yyyy-mm-dd forma from that t, that would work, but I do not know how to do coding in MS Access. 

How can I format the data that is input into the form to be the yyyy-mm-dd format?

I have tried changing the display and data format through livecycle patterns for the field, but that is not working.

Any assistance would be greatly appreciated!

Thank you