I know you guys frown at the use of registry cleaners, but I downloaded a limited trial version of RegCleaner last week. As I think I mentioned in an earlier thread, when I ran it, it detected a couple of hundred anomalies in my computer. It would only clean 31 of them, but in doing so it cleared 90% of a problem which had been dogging my computer for a few years, namely an apparent sticking or searching problem, were the hard drive would do nothing for a couple of minutes other than make a rythmic sound. That has now largely disappeared, so I would love to receive some informed opinions as to why that should be, if only to satisfy my curiosity. One thing I have noticed, and this is coming from a totally beginners perspective, is that when I did a scan with Treesize, it detected an awful lot of .DAT files which wouldn't delete. They've now gone. Just a thought.