Comments - Dammo

Hi, I registered specifically to add something to this bcdedit.exe suggestion.

In my case, when I rebooted my laptop (a Dell Inspiron 1720 running Vista Home Premium as the OS), it caused a big headache. Vista failed to boot. It would show the Dell logo, then flash with a blue screen (BSOD) for a moment, then reboot and load into a System Diagnostic tool. It would run diagnostics and disk scans and ultimately conclude that it could not find the problem, or that it was caused by unspecified system changes.
System restore did not help. (I had set a restore point immediately before making the bcdedit.exe change above).

The disk scan can be cancelled, which will allow you to proceed to some additional system diagnostic tools - including a command prompt.

SO, what to do?

First, I tried un-doing the bcdedit.exe command.
In the command prompt, I entered the following:

bcdedit.exe /set {current} nx AlwaysOn

Then I rebooted the laptop. Still not fixed... the blue screen continued.

Further research revealed the following suggestion:

bcdedit.exe /set {default} nx AlwaysOn

Then I rebooted the laptop, and it loaded into Windows Vista as normal. As if it were all but a dream...!