I have a lab running w7. a few weeks ago a few students had trouble when logging on. right after the login screen goes away the screen goes black with a cursor. I tried rebooting and eventually found if I waited 10-15 minutes the students screen would come up and they could work. At first it was different computers and different students, not always the same student or computer but once a student had the problem on that computer they always have that problem on that computer. I tried deleting the user folders to no avail. Now the whole lab is taking 10-15 minutes for logging on and we do not have that kind of time. Adults who log on and my admin logon do not have the same problem. I have looked everywhere online and can not find a fix that works. i tried one that i found but the download was no longer at that location. i have teachers unable to use the lab because classes are only 45 minutes.