File.InboundAdapter archives files missing or 0kb

Hi: 

I'm new to Cache and intersystems. 

We have a live production solution that uses a file inbound adapter to collect pdf documents off a fileshare. This fileshare is accessed by many services and access is controlled to the files by AD.

A problem we are seeing is that documents either are attempted to be processed with a filesize of 0kb or more often a file gets processed that in the next buisness process then cannot be moved to a working directory and the file does not appear in the archive from the file inbound adapter. It appears like the same file gets picked up by a later session but we have no way of knowing if it is the same doc or not. 

We had some errors previously that was corrected by changing the confirm complete to writeable.

Does anyone have any ideas? The file adapter isn't notifying us of the problem archiving the files.