Removing 12-hour time from Windows 10 login screen at startup (24-hour already set)

Question

So my problem is somewhat minute, and the main problem was addressed here, but when I first turn my computer on, it always shows the 12h format. The account I log into is the admin account, and once I log in (due to my settings), the lock screen shows 24h. But before I do, it always shows 12h.

It's not a huge deal, I just find it annoying since I think the 12h system is annoying to begin with if I'm not reading an analog clock. I'd guess there is some "default" value its adhering to (presumably the American ones Windows generally assumes by default) -- is there some sort of way to change this?

Answer 1

The ".DEFAULT" system internationalization settings can be found in the following registry key:

HKEY_USERS\.DEFAULT\Control Panel\International

Update the following values to match those of your user settings:

• sTimeFormat (likely: H:mm:ss)
• sShortTime (likely: H:mm)

Note: Your user settings can be found in:

HKEY_CURRENT_USER\Control Panel\International

Answer 2

PowerShell method:

New-PSDrive -Name HKU -PSProvider Registry -Root HKEY_USERS | Out-Null 
$internationalPaths = @("HKU:\.DEFAULT\Control Panel\International","HKCU:\Control Panel\International")
$hourFormat = "h"
IF($TimeFormat -eq '24h')
{
    $hourFormat = "H"
}       
FOREACH ($path in $internationalPaths)
{
    IF((Get-ItemProperty $path).'sTimeFormat')
    {
        #Windows 10 default time format h:mm:ss tt
        Set-ItemProperty -Path $path -Name "sTimeFormat" -Value "$hourFormat`:mm:ss tt"
    }
    IF((Get-ItemProperty $path).'sShortTime')
    {
        #Windows 10 default time format h:mm tt
        Set-ItemProperty -Path $path -Name "sShortTime" -Value "$hourFormat`:mm tt"
    }
}

More details How to change Windows 10 Lock screen time format by PowerShell