run bios from start up (normally Del key) and set to load default settings, re boot and press F8 for windows startup and choose last known good settings. This should help... If not you will need to have someone reinstall your operating system or repair operating system from OS Disc (not usually supplied). It may also be beneficial to look for help on reinstallation of system files using emachines software from their website.
David Hammond, January 2009
