Monthly Archive


Monthly Archives: January 2016

Scripting Game puzzle – – January 2016

Here’s how I’d solve the puzzle

function get-starttime {
        [Alias('CN', 'Computer')]
        [string[]]$computername = $env:COMPUTERNAME
        foreach ($computer in $computername){
            $props = [ordered]@{
                ComputerName = $computer
                StartTime = ''
                'UpTime (Days)' = 0.0
                Status = 'OFFLINE'
            if (Test-WSMan -ComputerName $computer -ErrorAction SilentlyContinue) {
                $lbt = Get-CimInstance -ClassName Win32_OperatingSystem -ComputerName $computer -ErrorAction SilentlyContinue
                if ($lbt) {
                    $props['StartTime'] = $lbt.LastBootUpTime
                    $upt = [math]::round(((Get-Date) - $lbt.LastBootUpTime).TotalDays, 1)
                    $props['UpTime (Days)'] = $upt
                    $props['Status'] = 'OK'
                else {
                    $props['Status'] = 'ERROR'
            } ## endif
            New-Object -TypeName PSObject -Property $props
        } ## end foreach
    } ## end PROCESS

Create an advanced function. Yes I know I’ve used lower case for the function name. I always do to visually separate my code from cmdlets and other functions.


Use the [parameter] decorator to enable pipeline input. Only a single parameter so don’t need to bother woth positional parameters. Function is supposed to default to local machien so can’t make parameter mandatory.


Requirement to process multiple computers at once presumably means the computername parameter has to take an array – sumultaneous processing implies a work flow which negates the initial requirement to create a function


Use the PROCESS block to run a foreach loop that iterates over the collection of computernames.


Create a hash table for the results – I’ve used an ordered hash table to preserve the property order. Set the values to a failed connection.


use Test-Wsman to see if can reach the computer. If can’t the output object is created. If you can reach the machine then run Get-CimInstance - preferred over Get-WmiObject because it returns the date ready formatted


Assuming that works set the start time and status properties. Calculate the uptime in days. I’d prefer to see  just an integer here – tenths of days doesn’t mean anything to most people


If the call to Get-CimInstance  fails then set the status to ERROR

Output the object.


The requirement to add a proeprty for patching is not clear but I’m assuming it means if the machine has been up for more than 30 days with the 1/10 month as a typo

if you want to add that then


Add a property

MightNeedPatching = $false

to the hash table when you create it


and add this line

if ($upt -ge 30){$props['MightNeedPatching'] = $true}


$upt = [math]::round(((Get-Date) - $lbt.LastBootUpTime).TotalDays, 1)
$props['UpTime (Days)'] = $upt

PowerShell Deal of the Day – – 31 January 2016

PowerShell in Action, Third Edition is Manning’s Deal of the Day Sunday 31 January 2016


Deal of the Day January 31: Half off Windows PowerShell in Action, Third Edition. Use code dotd013116au at


PowerShell in Depth, Second Edition is also available as part of the deal


Deal of the Day January 31: Half off my book PowerShell in Depth, Second Edition. Use code dotd013116au at


The deal will go live at Midnight US ET and will stay active for about 48 hours to account for time zones.

PowerShell editing options

I’ve used the ISE since it first appeared in PowerShell 2.0 but there are a couple of recent annocements that increase your code editing options


ISE previews will become available out of band rather than being tied to WMF/OS releases


The preview ISE is a module you can download from the PowerShell gallery and runs side-by-side with your existing version of ISE

Currently this is a PowerShell 5.0 only option

The current preview  hasn’t changed much – its just to test the delivery mechanism. Look for updates approximately monthly.


The second interesting editing option is Visual Studio Code which has PowerShell support


as well as a host of other languages. if you have to work across multiple languages this may be an option for you


Alternativley, if you use Visual Studio a lot you have the PowerShell Tools for Visual Studio option

Which filter

Get-ADUser has 2 filter parameters.

The –Filter takes a PowerShell syntax filter e.g.

Get-ADUser -Filter {Name -eq 'Richard'}

The –LDAPfilter takes an LDAP search filter e.g.

Get-ADUser -LDAPFilter "(Name=Richard)"

Mixing them up will ensure you don’t get the results you want

Rescuing IE favourites

I received the new Windows Insider Windows 10 build over the wekend and have just discovered that installing it wiped out my IE favourites – or at least those in folders.


I’d copied my favourites to Microsoft Edge when installing Windows 10 so I can copy everything back


IE favourites are stored at

Get-ChildItem -Path 'C:\Users\<user>\Favorites'


You can clean out the favourites:

Get-ChildItem -Path 'C:\Users\<user>\Favorites' | Remove-Item –Force


You will be asked to confirm the action.


Microsft Edge favourites are at

Get-ChildItem -Path 'C:\Users\<user>\AppData\Local\Packages\Microsoft.MicrosoftEdge_8wekyb3d8bbwe\AC\MicrosoftEdge\
User\Default\Favorites' –Recurse


Copy them into the IE favourites folder

Get-ChildItem -Path 'C:\Users\<user>\AppData\Local\Packages\Microsoft.MicrosoftEdge_8wekyb3d8bbwe\AC\MicrosoftEdge\
User\Default\Favorites' | Copy-Item -Destination 'C:\Users\<user>\Favorites' -Force -Recurse


Job done


How do you find the FQDN of the machine you’re using. 

The simplest way is to combine a couple of environmental variables:



If you like using CIM (and who doesn’t) you can try this

PS> Get-CimInstance -ClassName Win32_ComputerSystem |
>> select @{N='FQDN'; E={"$($_.DNSHostName).$($_.Domain)"}}



This could easily be used for remote machines as well by adding the –ComputerName parameter to Get-CimInstance


If you want to go down the .NET route you have:

PS> [System.Net.Dns]::GetHostByName('').HostName

CDXML filter parameters

I was recently asked about adding a filter parameter to a cmdlet created through CDXML. If you’ve not seen it before (see PowerShell and WMI Chapters 18 & 19 from CDXML allows you to creat ecmdlets by wrapping a WMI class in some simple XML.


The resultaing CDXML (Cmdlet Definition XML) is thn published as a module.  Here’s a simple example using the Win32_NetworkAdapterConfiguration class

<?xml version='1.0' encoding='utf-8'?>
<PowerShellMetadata xmlns=''>
  <Class ClassName='ROOT\cimv2\Win32_NetworkAdapterConfiguration'>
      <GetCmdletParameters DefaultCmdletParameterSet='DefaultSet'>


The first 2 lines are boilerplate. The NameSpace and WMI class are defined on line 3, follwoed by a version number (arbitary) and a default noun for you cmdlet to use.  Instance cmdlets defines how you’ll pull the data for existing instances of the class – in other words the Get-NetworkAdapterConfiguration cmdlet.


Save as a CDXML file and import as a module

Import-Module .\NetworkAdapterConfiguration.cdxml


Get-Module will sjow it as a Cim module with a single exported command.   Use it like any other cmdlet

PS> Get-NetworkAdapterConfiguration | ft -a

ServiceName  DHCPEnabled Index Description
-----------  ----------- ----- -----------
kdnic        True        0     Microsoft Kernel Debug Network Adapter
mwlu97w8     True        1     Marvell AVASTAR Wireless Composite Device
msu64w8      False       2     Surface Ethernet Adapter
mwlu97w8     True        3     Marvell AVASTAR 350N Wireless Network Controller
RFCOMM       False       4     Bluetooth Device (RFCOMM Protocol TDI)
BthPan       True        5     Bluetooth Device (Personal Area Network)
vwifimp      True        6     Microsoft Wi-Fi Direct Virtual Adapter
vwifimp      True        7     Microsoft Wi-Fi Direct Virtual Adapter
RasSstp      False       8     WAN Miniport (SSTP)
RasAgileVpn  False       9     WAN Miniport (IKEv2)
Rasl2tp      False       10    WAN Miniport (L2TP)
PptpMiniport False       11    WAN Miniport (PPTP)
RasPppoe     False       12    WAN Miniport (PPPOE)
NdisWan      False       13    WAN Miniport (IP)
NdisWan      False       14    WAN Miniport (IPv6)
NdisWan      False       15    WAN Miniport (Network Monitor)


Using the cmdlet is equivalent to

Get-CimInstance -ClassName Win32_NetworkAdapterConfiguration


but is easier and requires less typing.

Very often you’ll want to pick a specific adapter – for instance


Get-CimInstance -ClassName Win32_NetworkAdapterConfiguration -Filter 'Index=3'


You can implement the same kind of filters using CDXML. You add a queryable properties section as shown below:

<?xml version='1.0' encoding='utf-8'?>
<PowerShellMetadata xmlns=''>
  <Class ClassName='ROOT\cimv2\Win32_NetworkAdapterConfiguration'>
      <GetCmdletParameters DefaultCmdletParameterSet='DefaultSet'>

          <Property PropertyName='Index'>
            <Type PSType ='UInt32'/>
            <RegularQuery AllowGlobbing='true'>
              <CmdletParameterMetadata PSName='Index'  ValueFromPipelineByPropertyName='true' CmdletParameterSets='DefaultSet' />


Set the paraemter name – same as property to use here – and the type (unsigned integer). Decide whether pipeline input and wildcards (globbing) are allowed and save the file.


Re-import the module (use the Force) and your new parameter is available

Get-NetworkAdapterConfiguration -Index 3


Its important to understand CDXMLMI – even if you never create a CDXML module – because 2/3 of the cmdlets in Windows Server 2012 and later are created this way.

WMF 4.0 Updates available downlevel

The WMF 4.0 Updates that were released in November 2014 for Windows 8.1 and Windows Server 2012 R2 are now available for:

Windows Server 2012

Windows Server 2008 R2 SP1

Windows 7 SP1


You need WMF 4.0 installed to install the update


Details from

Setting external time source in AD

The PDC emaulator in the root domain of your AD forest should point to an external time source. For some odd reason the PDC emulator in my lab wasn’t doing that. Easily remedied:

## set external time source
## set server type to NTP
Set-ItemProperty -Path HKLM:\SYSTEM\CurrentControlSet\Services\W32Time\Parameters -Name Type -Value 'NTP'
Set-ItemProperty -Path HKLM:\SYSTEM\CurrentControlSet\Services\W32Time\Config -Name AnnounceFlags -Value 5
## Enable NTP server
Set-ItemProperty -Path HKLM:\SYSTEM\CurrentControlSet\Services\W32Time\TimeProviders\NtpServer -Name Enabled -Value 1
## Specify Time source
Set-ItemProperty -Path HKLM:\SYSTEM\CurrentControlSet\Services\W32Time\Parameters -Name NtpServer -Value ',0x1'
## Set poll interval in seconds - every 30 minutes
Set-ItemProperty -Path HKLM:\SYSTEM\CurrentControlSet\Services\W32Time\TimeProviders\NtpClient -Name SpecialPollInterval -Value 1800
## set max +/- time corrections in seconds - 24 hours
Set-ItemProperty -Path HKLM:\SYSTEM\CurrentControlSet\Services\W32Time\Config -Name MaxPosPhaseCorrection -Value 86400
Set-ItemProperty -Path HKLM:\SYSTEM\CurrentControlSet\Services\W32Time\Config -Name MaxnegPhaseCorrection -Value 86400

Stop-Service -Name W32Time
Start-Service -Name W32Time


Wait a minute or so and the time will be set correctly.


Not a job you have to do very often but having the code to do the job reduces the probability of errors

You can view the settings

Get-Item HKLM:\SYSTEM\CurrentControlSet\Services\W32Time\Parameters
Get-Item HKLM:\SYSTEM\CurrentControlSet\Services\W32Time\Config
Get-Item HKLM:\SYSTEM\CurrentControlSet\Services\W32Time\TimeProviders\NtpServer
Get-Item HKLM:\SYSTEM\CurrentControlSet\Services\W32Time\TimeProviders\NtpClient

WMF 5.0

If you follow the PowerShell Team blog - (and if you don’t you should) you’ll know that the WMF 5.0 RTM downloads were pulled just before Christmas. This was due to a bug that reset the module environment.


A comment on the blog - – from the team indicates that it’s likely to be a few weeks before the bug is resolved and WMF 5.0 is available again for download.