"J. P. Gilliver (John)" wrote

| Thanks, you and Ed. Excellent idea. Then I found my Process Explorer
| won't work! I've extracted it again from the .zip file I downloaded (and
| yes, it _did_ work then!); I run it, I get the UAC popup, I click Run in
| that, and - nothing happens. And there's nothing beginning with P in
| Task Manager other than Panorama.

Sounds fishy to me. Your software generally
works but editing HOSTS and running ProcExp
are blocked? I'd suspect some kind of sneaky
thing had got onto the system.

If it were me I'd first shut off UAC and if that
didn't clear things up I'd try downloading some
malware/AV products. (Many of them can be
downloaded as free packages for emergency use.)

The only other thing I can think of would be if you
had somehow screwed up file restrictions.... maybe
logging on as Guest or some such? But you have a
lot of experience. I can't think of anything you
might have done accidentally.
It's an interesting mystery.