Hi all, I installed Windows 7 Ultimate on my Dell Dimension 9150 a few days ago and applied the Microsoft language pack to translate it in French. Since the beginning, I have the same problem : randomly, the system partially "freeze" during about 10 seconds. I can't open any new window, can't type text and can't scroll down a webpage. At the same time, if there is music or a video playing, the song or the movie goes on like a charm. I've done all the windows update and scanned my computer with Eset Nod32 (no virus found) and Windows Defender (nothing found). The event viewer logs the 2 same events at every "freeze" : 1) Microsoft Windows security auditing ; event ID : 4624, Open session 2) Microsoft Windows security auditing ; event ID : 4672, Opening special session ( my account is admin). So it seems that the system "re login" by itself ? Do you have any clue on that problem ? Thanks a lot !