CA Traveler wrote:
No password required in Safe Mode so does this suggest that some driver, etc is responsible and is there any way to narrow down the problem?
This suggests that some program running at startup is hijacking some of your processes. Go back to safe mode and run msconfig. Disable all the startup programs. Boot back into normal mode and test your task manager or regedit. If they work without prompting for a password, start enabling your startup programs one at a time, testing after each one until you find the culprit.
Please post back here when you find the offending program.