Thanks for your advice ylp88 and andypro..
That all makes sense -it's just that the folder colours presented on my system here don't follow that convention at all! Sometimes folders can be all pink as you describe, but sometimes there are also random variations which I know are -definitely- not applicable!
Incidentaly, I havn't deleted Cookies at all in recent times, but from your comments I guess I'll just have to put it down to the possibility that the security software being used to guard against internet nasties is having an influence on cookie-processing beyond what was expected.
Maybe another factor might be that this PC turns off via Hibernation sometimes, & at other times is powered down in the normal manner after all programs are maually closed.
One of those things I'll have to put on the 'to-do' list to look into further, -even if just to satisfy my curiosity!
Thanks,
whizzer