[Tutorial] Software Poweroff in Windows NT 3.51

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[Tutorial] Software Poweroff in Windows NT 3.51

Post by 3155ffGd »

For some reason I don't see this mentioned anywhere so I will post about it.

Normally Windows NT 3.51, like most Windows NT operating systems, don't support software poweroff and will just leave you hanging on a "It is now safe to turn off the computer" screen forever. The Windows NT 4.0 solution has been known about for a while, but turns out, there's another solution for Windows NT 3.51 too that no one ever mentions on the Internet.

As it turns out, Fujitsu actually bothered to write a HAL for Windows NT 3.51 that supports Software Poweroff for their Fujitsu FMV personal computer. This computer is sufficiently compatible to a regular PC that the HAL will work in any virtual machine (and presumably on real machines too).

What you need:

1. Download halfmv0.dll. I conveniently dropped this file on my Google Drive: https://drive.google.com/open?id=1gK0PG ... eQfJ_ZCAUt
2. Start up Windows NT 3.51.
3. Replace the hal.dll that is present in the SYSTEM32 folder with the halfmv0.dll you just downloaded.
4. Reboot the system.
5. Add the appropriate registry key: open REGEDT32 (via File -> Run), navigate to the registry key HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon and look for the entry PowerdownAfterShutdown, which should be set to 0. Set it to 1 (it takes effect immediately).

If everything worked correctly the Shutdown dialog will have a new option "Shutdown and Power Off", which powers off the computer if selected.

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Re: [Tutorial] Software Poweroff in Windows NT 3.51

Post by scubasteve »

Black Screen for me, then restarts

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