FileSystemWatcher Created Event not Firing

Hi all

I've created a FileSystemWatcher which misses certain creation events. If I copy/paste a file into the relevant folder it works fine. If I do :

type [filename].txt > newfile.txt 

...it works fine. However when a file is uploaded from an FTP client via IIS7 FTP to the relevant folder (that being the root folder of an IIS FTP site), the creation event just doesn't fire at all. It's not a permissions problem. I just can't figure it out at all. This is on Windows 2008 with .NET 4.0. Appropriate code is below :

            this.fileSystemWatcher_Dropzone.EnableRaisingEvents = true;
            this.fileSystemWatcher_Dropzone.Filter = "*.wav";
            this.fileSystemWatcher_Dropzone.IncludeSubdirectories = true;
            this.fileSystemWatcher_Dropzone.Path = "D:\\shared\\FTPDropZone";
            this.fileSystemWatcher_Dropzone.Created += new System.IO.FileSystemEventHandler(this.fileSystemWatcher_Dropzone_Created);

Any suggestions ?

Thanks

Pete