After all items in Control Panel would not open and some other small annoyances like not booting proberly at times, but all programs (Word, fs9, brodband, faxing etc) working fine, I followed all your instructions.
Finally ended up with the HD util's "Pwermax" test saying "...The drive is failing and must be replaced. Backup all and note this diagnostic Code.......".
Could this behaviour occur due to failing (6m old) HD, or can viruses do this? Some files detected by Adware were cleared.
I was always running firewalls, antivirus end never brought emails in to the HD, always read them on server.
As had nothing further to loose I practiced with all HD tools available and finally managed to write Zeros succesfully. Now the HD is recognised by all utils.
The dilemma is, do I return it to the local shop who agreed to replace it, or do I carry on with rebuilding to where it was?, and stay with the devil you know sort of thing.
Anybody experienced similar problem before, to advise me? luke