Trying to Export a CSV list of users using Active Directory Module for Windows Powershell - excel

Question

So the below is where I'm at so far:
import-module activedirectory
$domain = "ourdomain"
Get-ADUser -Filter {enabled -eq $true} -Properties whenCreated,EmailAddress,CanonicalName |
select-object Name,EmailAddress,CanonicalName,whenCreated | export-csv C:\Data\test.csv
Unfortunately, when I run the above I get dates in two different formats in the CSV, e.g.:
01/01/2017
1/01/2017 8:35:56 PM
The issue this poses is that there isn't really a clean way to sort them. Excel's formatting doesn't change either of these formats to be more like the other, both because of the inclusion of time in one and not the other, and because the time-inclusive format doesn't use trailing zeroes in the single digit numbers, but the time-exclusive format does.
We have an existing script that captures users using the LastLogonTimestamp attribute that does this correctly by changing the bottom line to the following:
select-object Name,EmailAddress,CanonicalName,#{Name="Timestamp"; Expression={[DateTime]::FromFileTime($_.whenCreated).ToString('yyyy-MM-dd_hh:mm:ss')}}
For some reason this expression runs properly when we query the LastLogonTimestamp attribute, but when we run this version querying the whenCreated attribute, we get an entirely blank column underneath the Timestamp header.
I'm not particularly knowledgeable about PowerShell itself, and my colleague who had found the original script for the LastLogonTimestamp just found it online and adapted it as minimally as possible to have it work for us, so I don't know if something in this line would work properly with one of these attributes and not the other. It seems strange to me though that two attributes using dates in the same program would store them in different formats though, so I'm not convinced that's it.
In any case, any help anyone can offer to help us get a uniform date format in the output of this script would be greatly appreciated - it needn't have the time included if it's easier to do away with it, though if they're equally easy we may as well keep it.

Answer 1

whencreated is already a [DateTime]. Notice the difference between the properties when you run something like this:
Get-ADUser TestUser -Properties lastlogon,whenCreated | select lastlogon,whenCreated | fl
(Get-ADUser TestUser -Properties lastlogon).lastlogon | gm
(Get-ADUser TestUser -Properties whenCreated).whenCreated | gm
This means that you don't have to convert to a DateTime before running the toString() method.
select-object #{Name="Timestamp"; Expression={$_.whenCreated.ToString('yyyy-MM-dd_hh:mm:ss')}}