Convert text to "mm/dd/yyyy hh:mm:ss" format

Is it possible to get a macro to convert the values on column D and E to "mm/dd/yyyy hh:mm:ss" format.

Attached the workbook. Currently the values are shown as text and I was not able to change them any other way. Text to Columns will not work for me as it requires inserting new columns

I tried at Excel General but didn't really find a solution that I can use for what I wahttp://www.excelforum.com/excel-gene...ates-time.html

I think a code will be the best way to do it. Will appreciate any help.