I have seen this msg when windows 7 boots after SysPreped using Audit Mode.
“Windows could not complete the installation. To install Windows on this computer, restart the installation”
having googled around below is fix that worked fine for me.
When prompted with error unable to complete installation:
Hit SHIFT-F10 to bring up command prompt.
Click File -> Add/Remove Snap-in… (Or CTRL+M)
Select Computer Management (Double click and Finish on Local Computer)
Double click Computer Management (Local) -> System Tools -> Local Users and Groups -> Users -> Double Click Administrator -> Uncheck Account is disabled -> OK
if it gives you error about password. then first SET A Password , then Uncheck this button.
Now right click Administrator -> Set Password… -> Set a decent password to get started.
Close all these windows without saving settings to MMC. hit OK to that msg it will restart or use just reboot anyhow.
after restart. Should boot up fine and prompt saying password incorrect as it tries to login with inbuilt account, you just need to login with defined password.
hope this will help someone