You MUST process the files in the UploadFinished event. The temporary files that back the uploads are deleted when that event finishes.
I suggest that instead of passing around that array, that you copy the FolderItems (with Folderitem.CopyTo) to a new location on disk and then process them.
it seems that the processing of files block the web application, thats why i put the process in a thread. i saved it all in this UploadFinished before.
for my needs i want this files in database as postgre large objects.
i will test your suggestions later. thanks.