Question

As topic states. How can I put 1 extra day to the selected user account.

I know AD goes by Windows File Time. Does anyone know the easiest and least code written method?

Answer 1

You can modify the accountExpires property of an AD user through the Set-ADUser cmdlet included in Windows Server 2008 R2:

Import-Module activedirectory

$expireDate = (Get-ADUser -Identity "John Appleseed" -Properties accountExpires).accountExpires
$renewedExpireDate = ([System.DateTime]::FromFileTime($expireDate)).AddDays(1)

Set-ADUser -Identity "John Appleseed" -AccountExpirationDate $renewedExpireDate

As you said, the value of the accountExpires property is represented as a Windows file time, which is a 64-bit integer. In this example we convert it to a DateTime to easily modify it and then pass it to the -AccountExpirationDate parameter to update the user.