What did you do or what changes did you make to your computer since all operated fine? Bad things just do not happen - you must have done something that is now responsible for the issue. Can you repair your Vista installation - your OS may be at issue. If you have other computer with Vista try installing there to see if it works. Maybe something is now wrong with the camera - it happens.
Set shake reduction, if your camera has it, or else use a tripod or other support. Increase ISO so you can use a faster shutter speed and smaller aperture, for greater depth of field. Use manual focus if you can - night scenes often confuse autofocus. Finally, be prepared for a high failure rate !
The problem is that the lens has become stuck in the barrel. There are some DIY solutions you could try, but the
probability is that you will have to get it fixed by a professional.
these at own risk as it may further damage the camera.
try connecting your ac adapter or usb cable.
Try holding the
shutter button while switching on the camera.
Look at the lens ,
and if some of the lens 'circles' is misaligned or not concentric then
try wiggling it (while holding camera lens down).
pushing or pulling the lens when it extends but this is risky as it may
cause the lens barrel to slip out of its guidance system.
way to do this is to place the camera lens down on a hard surface and
then power it up. Be sure to use a soft cloth or something similar as to
not scratch your lens or casing. Let the lens push the camera up and
down a few times and sometimes the little resistance provided by the
camera is enough to get things going again.
Try hitting your
camera near the lens on the body with the soft tissue on the palm of
Other than that , I would take the camera to a repair
center for a evaluation to see if it would cost more to repair than to
replace the camera.
If it is still under warranty I would suggest
you take it in before trying any of these steps and remove any
off-brand batteries or accessories as some stores are really fussy about
warranty repairs on camera's with non-brand accessories.