Profile logon failed >> logonUI.exe corrupt >> impossible to logon even in safe mode

[david.cooper.esq]

My HP Touchsmart running Vista Home has multiple severe logon problems...

Initially it was the error "The User Profile Service service failed the logon. User profile cannot be loaded" after starting up.

I tried a system restore but there was only one restore point with today's date. (Although I've used system restore successfully in the past). Going back to this restore point resulted in a "catastrophic failure".

I then went into safe mode and tried correcting the (one and only) administrator profile using regedit, as suggested on the Microsoft forum. This didn't help.

When making further attempts to logon, I started getting messages about logonUI.exe being corrupt. Now I can't logon even in safe mode. Just says "Welcome" and stalls.

Repairing Vista using the DVD isn't an option because I didn't receive one, just the factory files - which I can use to do a fresh install but will lose all my files and intstallations in the process.

Any advice greatly appreciated.

+ dave