Your command that determines the currently highest uidNumber is broken; replace it with the following:
[int] $lastuid = (
Get-ADUser -Filter * -searchbase $searchbase -Properties uidnumber |
Measure-Object -Property uidnumber -Maximum
).Maximum
Note:
(...).Maximum, i.e. direct property access is used to obtain the maximum value from the Measure-Object call.
- There is no need for
select (Select-Object), and especially not Format-Wide - see next section.
There's no need for filtering out $null values with a Where (Where-Object) call, as Measure-Object will simply ignore them.
Using -Properties * is expensive and best avoided; here, you only need one non-default property, uidnumber.
A separate problem is that your code for updating the uidnumber field doesn't increment the number for each targeted user: [int] $i + 1 assigns the same value to all; the simplest solution is to use ++:
$noUid | Set-ADUser -replace @{ uidnumber = ++$i }
Note:
- There is no need for
% (ForEach-Object), as you can pipe the user objects stored in $noUid directly to Set-ADUser.
There's potential for additional optimization of your code, such as calling Get-ADUser -Filter * only once, assuming that all users objects fit into memory at once:
$withoutUid, $withtUid =
(Get-ADUser -Filter * -searchbase $searchbase -Properties uidnumber).
Where({ $null -eq $_.uidnumber }, 'Split')
[int] $lastuid = ($withUid | Measure-Object -Property uidnumber -Maximum).Maximum
$withoutUid | Set-ADUser -replace @{ uidnumber = ++$lastuid }
As for what you tried:
Format-* cmdlets such as Format-Wide emit output objects whose sole purpose is to provide formatting instructions to PowerShell's for-display output-formatting system. In short: only ever use Format-* cmdlets to format data for display, never for subsequent programmatic processing - see this answer for more information.
- Apart from
Format-Wide not representing the data you intended, it output multiple objects, which $lastuid = ... captured in an array. It is that array that caused the error you saw.
Omitting Format-Wide wouldn't suffice in your case, because select maximum (Select-Object maximum) also wouldn't work as intended: it would create an object with a .Maximum property, instead of directly emitting the value of the .Maximum property of the property returned by Measure-Object. For the latter you need Select-Object -ExpandProperty maximum - see this answer for more information.
