Recently my company decided to turn off file transfer through federation while leaving it on internal. We did not think this would be of much notice but did not have much insight on what kind of traffic this modality had. After turning it off it only took about a week for the complaints to start rolling in. This leads to my current development effort. I have created a MSPL script to capture the file transfer on my edge server and everything is great there. I am now trying to create a UCMA application that will sit and listen and when called would intercept the message, copy the file and download it, then send it back on to its intended recipient. I guess I underestimated how difficult this would be. It looks like for mediatypes there is not one even in the API for file transfer. Talking to MS they said I would need to extend out the API. I have done this so far to include the file transfer as a mediatype. But I need help in trying to extend whatever handler I need to use to listen and notice that a file transfer is happening. Can anyone assist in this?