I've shifted a lot to the back-up HDD until I need it again, and have now got up to 17%, but using cclean and defrag is not making a lot of difference to the "red", and I have carried out 4 or 5 defrags.

Logmon is another with a big fragmentation. Strange this, as a month or so ago, I had only a few fragmented files, and now quite a few.

I'll keep with it and defrag as often as I can to try to clean up the disk.

Thanks for your help and advice.