Like a fool, I have used the compress old files feature in disc cleanup:( all I have now managed to do is slow down my system boot up, which can now take upto 3-4 mins, compared to the initial 1 min. Can I reverse this error? if so what can I do? I have noticed if I click on my windows folder, and right click - properties - advance, this says "compress files to save space" would un checking this work? My Dell notebook does not have this checked. Please help Stuart