I have noticed this problem happens (and it's a real headache!) whenever I try to open a directory having a fairly large number of really big files, as in the case of the receiving folder of a p2p application. If that folder has, say, more than 150 files and the average file size is about 40MB or more, I'll probably get Win Explorer.exe to "hang" while trying to open the folder, taking up to 10 minutes at a 99%--100% CPU utilization to show the folder's file list. (What a waste of MY time and MY computer's resources!). Curiously enough, when an instance of explorer.exe gets started as a "hijacked app", for example, when I order the p2p application to open the incoming folder (starting a new instance of explorer.exe) then Windows Explorer behaves, and shows the folder's contents instantly. If for any reason I do not want to open it that way (i.e., I really don't want to start the p2p app just to see the incoming folder) I've found a snug replacement utility, the Fileant file manager, to do a nice job. If you have McAfee Securuty Suite, just ignore warnings that Fileant is Spyware or the like -- they're just rubbish.