Thanks for your welcome street1 and also the tip.
No I haven't yet tried system restore.
What data would I lose by doing that?
Do I need to download programmes and data to a USB key first?
GX1_Man. Thanks for your help.I cannot remember anything specific before it happened.
I noticed it when I tried to copy a CD using Roxio Easy CD creator which I had previously used many times with no problems. As I don't copy CDs very often, whatever it is that is blocking the drives, probably happened many weeks or months prior to me attempting to copy the CD.
Would it possibly be a conflict with two different media players on the system?