I've tried a few variations of this...

The File System task operates on a single file or directory. Therefore, this task does not support the use of wildcard characters to perform the same operation on multiple files. To have the File System task repeat an operation on multiple files or directories, put the File System task in a Foreach Loop container, as described in the following steps:

Configure the Foreach Loop container On the Collection page of the Foreach Loop Editor, set the enumerator to Foreach File Enumerator and enter the wildcard expression as the enumerator configuration for Files. On the Variable Mappings page of the Foreach Loop Editor, map a variable that you want to use to pass the file names one at a time to the File System task.

Add and configure a File System task Add a File System task to the Foreach Loop container. On the General page of the File System Task Editor, set the SourceVariable or DestinationVariable property to the variable that you defined in the Foreach Loop container.

...found here...

https://msdn.microsoft.com/en-us/library/ms140185.aspx

...but it's still not working.