Acrobat 8.0 professional

I have used acrobat 5.0 so far. I have to attach pdf files using a web based browser to a document management system. And once attached the web browser deletes the pdf file in the originating folder. However, acrobat 8 does not allow me to do that due to the fact that it locks the file in the originating folder. Does any one know how I can disable the locking mechanism with acrobat 8.0 Thanks very much