It isn't digital file pro. We used that exact object for years on the webassist forum and never had a problem.
What is the exact text of the error. You might be able to get a more recent version of the Persits upload object which may correct the problem. Do their samples still use: Server.CreateObject("Persits.Upload.1")
Since we have released version 2 with only php support we don't update the asp or cfml versions any more, but I don't think this is actually a problem with the code in the extension anyway.