Answer
The user account running the Data Delivery Extension (DDE) requires read/write permissions to the location being used to store the translation results; for example: C:\Inetpub\wwwroot\results.
The Data Delivery Extension needs to create and write the according results files and temporary subdirectories into this location. It compresses the results files and then deletes the temporary subdirectories and files from this location.
The Web server only requires read access to the location being used by
the DDE to store the translation results so that it can download the results to the according end user once they become available.