Thanks Malke. I have read through the links.

I suspect the likeliest cause is Norton Internet Security 2007. The only
reason I like that edition (and they did issue a Vista version) is because,
in accessing a website that carries advertisements flashing all over the
place, NIS 2007 add-on pack has a web advert blocker that is reasonably
efficient. I suspect they were "persuaded" to not include it in the 2008
edition.

I have also checked through your website which has much of interest to me.

"Malke" wrote:
[color=blue]
> Tony UK wrote:
>[color=green]
> > Malke
> >
> > As ever I admire your targeting the problem.
> >
> > My only comment is that, using Vista, I have tried a number of times to
> > use System Restore. About 75% of the occasions, it refuses to restore. I
> > don't understand why thiss should be so. Do you have any general advice on
> > this subject?[/color]
>
> I'd look on MVP Bert Kinney's site to see if anything there is applicable to
> your situation.
>
> MVP Bert Kinney on System Restore - [url]http://bertk.mvps.org/html/vista.html[/url]
>
> Problems caused by Symantec - [url]http://bertk.mvps.org/html/symantecdoc1.html[/url]
>
> System Restore - Error Messages in Vista -
> [url]http://bertk.mvps.org/html/eerrormsgsv.html[/url]
>
> Missing Restore Points/Shadow Copies in Windows Vista -
> [url]http://bertk.mvps.org/html/missingrpv.html[/url]
>
> Or if you have a Gateway - Can't use System Restore with Gateway Computer
> (Jill Zoeller, MS) - Go to System in Control Panel and open the System
> Protection tab. Do you see a drive called "Missing"? Selecting C:\ and
> deselecting "Missing" will allow the system to take restore points
> normally. Note that you will not have any restore points to restore to
> until a new restore point is made.
>
> Or you could post in the System Restore forum on AumHA:
> [url]http://aumha.net/viewforum.php?f=54[/url]
>
> Malke
> --
> MS-MVP
> Elephant Boy Computers
> [url]www.elephantboycomputers.com[/url]
> Don't Panic!
>[/color]