Hi and thanks for the replies.
Brianzion - Thanks for the links, I will go and read up but must admit that, when I was unsuccessful in getting it to work previously, I got very confused after reading all the tutorials around.
Simmo - I guess I have to agree! I gave up previously and it is only because this function has worked since I reinstalled Win 7 (and as a result I have grown accustomed to it working) that I am really keen to restore it now.
Hi Hopalong, yes I did tick "Show other restore points" but they are all missing

, but thanks anyway
I will write again if I have any success,
best regards to all,
Roger