Custom Expression under view as->File

So under the Fields tab, I select the LetterFile properties and go to view as select file and then check Show Custom Expression and enter:


$value = 'Download';
$file['usrName']= $data['LetterFile'];
$file['size']= filesize($data['LetterFile']);
$file['type']= mime_content_type ($data['LetterFile']);



To clarify things, $data should contain all columns from my sql table I'm referencing which makes LetterFile valid. LetterFile is the column name that stores the UNC path(with filename) as nvarchar.


But when I build the page out it displays a blank for the file. Not much else in the documentation to go by what am I missing?


I have already confirmed my web server has the proper access and can read/write to the directory LetterFile is refferencing.