I cannot get the machine to boot up. When I push the power button it begins to come on. The monitor shows a screen with the Electric Energy saving logo in the top right corner, then a screen with the tech. build of the computer (this is the regular start sequence), then it goes to a black blank screen (as in dos) with writing in the top left corner that says "A disk read error occurred, Press Ctrl+Alt+Del to restart". When I do that it begins a loop back to the start up screen. I was able to get into the BIOS and change the boot order to open with the CDROM. I let it boot off of the new Norton Anitvirus CD that I successfully loaded the day before this happened. That takes it into an emergency program that it runs and it returns that there is no virus and everything is clean. Then when I go out of this to start, it goes to the "read error" screen and loops back again. The hard disk light flashes showing activity. This problem started after the computer had been turned on and booted up to the regular desktop screen, but I could not get the task bar to pop up. When I took the cursor off the screen it would not come back. The keyboard was also locked out. Nothing would work. I re-booted and as it restarted a "Microsoft blue" screen came up saying something about there being an error and the computer was correcting something. I think it said there was an error in line (944) of something, and then it scrolled rapidly down the screen with line nuumbers, went blank, and started the "read error" loop. Nothing has worked since then. As I said, I had installed a new Norton Anitvirus program the day before this. My subscription had run out and I bought a new program. I had to completely uninstall the original Antivirus program to be able to load the new one. Everything showed that this was all successful. There have been no other changes lately.