Hello Maria
No I hadn't so I went to Actons/Restart but the restart icon wasn't highlighted so I couldn't do it.
I closed every thing down including my iMac - restarted every thing and windows fired up this time - all good now
I did notice yesterday the CPU was @ 100% when checking Parallels not sure if this had to do with something from stopping Win10 from opening.
Anyway fingers crossed, i'll save you email as a reference should it stall ageing
Thanks for your help
Colin