Windows XP Sp1 networked through a Speedtouch 510 4 port modem/router. Since applying Sp1 at the weekend the computer has hung at start up with 'Windows is starting up' on the screen (will occasionally start up). Hangs at shutdown especially if you log off the account first. I have applied the update 822603 which replaces the usb drivers installed by Sp1 and I have run Symantecs W32.Welchia.Worm tool. I have tried disconnecting all usb devices apart from the cordless keyboard and mouse. It seems to connect more easily when unplugged from the network but this may be a red herring. The network settings are manually configured so that I can use the attached printer from a mac also on the network. Anyone have any ideas?