I've got a small network with a Windows Server 2012 and several PC's. One of these gives me trouble. It's a machine with Windows 8.1 WMC. Personal files of the user of this machine are on the server. This works with a folder redirection policy. This always worked nicely but since the update to 8.1 the user can not always get his files. It then takes a long time to get the folders and files displayed in file explorer and when they are, he cannot display a picture. After a timeout this error gets displayed: "There has been an error. The photo or video cannot be displayed. Errorcode 0x80004004". Copying the same file to his own computer works fine. Sometimes the file explorer freezes and eventually the desktop resets. Only a restart of the Windows 8.1 computer resolves this problem. But it returns, sometimes only once a day, sometimes more often. There are no events that point to this problem. Any hints are welcome.