Ok, I've got Windows 2000 Professional with Service Pack 4 installed. In the last week I've started having some strange problems. Firstly, I noticed that in Internet Explorer (version 6) I can no longer right-click on a link and choose "Open in a new window". Well, I can choose it, and it does open a new window, but there's nothing in it; just a blank Internet Explorer window. Also, I can't copy and past folders/files. I can't drag and drop anything, in any application, including Windows Explorer. My network icon has disappeared from the system tray. Start-Settings-Network and Dial-up connections is empty - ie my network connection has disappeared, yet I am still connected to the network (ie at work). DCOMCNFG won't run either... it just uses 99% CPU time and never appears; I've left it for at least an hour, and it doesn't give an error message, it just never succeeds in displaying it's UI and keeps using 99% cpu time. I've tried installing/uninstalling/re-installing various windows updates (including windows 2000 service pack 4). I've tried re-installing Internet Explorer. Logging on as a different user doesn't help. Being on or off the network doesn't help. Anybody got any ideas? Thanks.