Every time I turn on my computer it goes to a black screen with a flashing cursor in the top right and does nothing else...how can I fix this?

have you had a virus recently? if so that maybe your cause,
try booting it in safe mode (hit F8) when you boot it up. this may enable you to enter the normal start-up routine.

it could be a virus, but have you installed any software? or it could be a corrupt registry, try to boot at last known good configuration.. what is your OS?

i had same problem with my pc figured it was doa, i have another computer now and well this one was working great two days ago i went to start it up and it boots into cmos/bios setup utility cant get it any further, the cmos says both my drives aer active, mem active and so on i even removed both hd and put a third in just to rule out that idea, changed cmos battery and still cant get it to boot it is a emachine 2.6 ghz system 1 gig ram need help, also new to this board so dont know yet how to check messages so cabon copy an email to me direct also with any helpful hints to maddmax0z@yahoo.com