I have a user that has been downloading PDF files and is unable to open them because they are corrupt. This does not happen all the time to the user, but he is the only one in his department with this problem. The others would download the same file and is able to open the same file. He has the latest version of Adobe Reader and updates. Something new that I have done is install a 4 port giga bit switch which he needs for a network printer in his office. Could the PDFs being downloaded have anything to do with that new switch I installed? Or could it just be a problem with Vista?