Using the F8 option.
An F8 boot option introduced with Windows Vista—“Disable
Driver Signature Enforcement”—is available to disable the kernel-signing enforcement
only for the current boot session. This setting does not persist across boot sessions.
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Setting the boot configuration.
A boot configuration setting is available for
prerelease builds that allows the suppression of the enforcement module in Windows
to be persisted across boot sessions.
Windows Vista includes a command-line tool, BCDedit, which can be used to set this option.
To use BCDedit, the user must have Elevated User or Administrator privileges on the system.
The most straightforward approach is to create a desktop shortcut to cmd.exe, and then
right-click -> Run Elevated. The following shows an example of running BDCedit at the
command prompt: // Disable enforcement – no signing checks
Bcdedit.exe –set nointegritychecks ON