Making this edit will require you to alter the code for the upload file function and is not a supported feature of DFP. It will be up to you to ensure that you implement it correctly. The first thing you should do is backup the current WA_DigitalFilePro > HelperPHP.php file in case you need to revert back.
Next you will open this file up and do a search for the following line of code:
php:
$attemptedFileName = str_replace($existingFileNameDefault, $baseFileName, $attemptedFileName);
When you find this line of code add a new line just underneath it and put this code in the new line:
php:
$attemptedFileName = str_replace(" ", "_", $attemptedFileName);
This will alter the name of the file and replace the spaces with underscores, this should make it match what you are inserting into your db.
