Remote registry key extractor PowerShell script - powershell

Question

I am trying to create a PowerShell script that remotely checks each machine on the domain for a registry key entry, then outputs that key value along with the machine name to a .csv file.
So far the script outputs all the machines on the domain to a .csv file but puts its local registry key value not the value of the remote machine.
Any help would be greatly appreciated, here is what I have so far.
Import-Module ActiveDirectory
$SRVS = Get-ADComputer -Filter * -SearchBase 'DC=mydomain,DC=local' |
select dnshostname
foreach ($SRV in $SRVS) {
$REG = [Microsoft.Win32.RegistryKey]::OpenRemoteBaseKey('LocalMachine', $SRV.name)
$REGKEY = $REG.OpenSubKey("SOFTWARE\Microsoft\Windows\CurrentVersion\QualityCompat")
$MELT = $REGKEY.GetValue('cadca5fe-87d3-4b96-b7fb-a231484277cc')
"$($SRV);$($MELT)" | Out-File C:\Users\user1\Desktop\regkeys.CSV -Append
}

Answer 1

The statement
$SRVS = Get-ADComputer ... | select dnshostname
gives you a list of custom objects with only one property: dnshostname. But in your loop you're trying to use a property name, which those custom objects don't have. Hence the statement
[Microsoft.Win32.RegistryKey]::OpenRemoteBaseKey('LocalMachine', $SRV.name)
effectively becomes
[Microsoft.Win32.RegistryKey]::OpenRemoteBaseKey('LocalMachine', $null)
meaning you're opening the local registry, not the registry on a remote host.
Change $SRV.name to $SRV.dnshostname and the problem will disappear.

Answer 2

Once it's been instanced the RegistryKey class does not expose that it's a remote key. That means you have to record the computer name yourself. There's also no standard format for a remote registry value.
If I had a PowerShell v5+, I would use something like this:
Import-Module ActiveDirectory
# No need for the Select-Object here since we're using $SRV.Name later
$SRVS = Get-ADComputer -Filter * -SearchBase 'DC=mydomain,DC=local'
# Create an arraylist to save our records
$Report = New-Object System.Collections.ArrayList
# This try finally is to ensure we can always write out what we've done so far
try {
foreach ($SRV in $SRVS) {
# Test if the remote computer is online
$IsOnline = Test-Connection -ComputerName $SRV.Name -Count 1 -Quiet;
if ($IsOnline) {
# If system is Online
$REG = [Microsoft.Win32.RegistryKey]::OpenRemoteBaseKey('LocalMachine', $SRV.name)
$REGKEY = $REG.OpenSubKey("SOFTWARE\Microsoft\Windows\CurrentVersion\QualityCompat")
$MELT = $REGKEY.GetValue('cadca5fe-87d3-4b96-b7fb-a231484277cc')
# Create a PSObject record for convenience
$Record = [PSCustomObject]#{
ComputerName = $SRV;
Key = $REGKEY.Name;
Value = $MELT;
}
}
else {
# If system is Offline
# Create a PSObject record for convenience
$Record = [PSCustomObject]#{
ComputerName = $SRV;
Key = '';
Value = '';
}
}
# Add our record to the report
$Report.Add($Record);
}
}
finally {
# Always write out what we have whether or not we hit an error in the middle
$Report | Export-Csv -Path "C:\Users\user1\Desktop\regkeys.csv" -NoTypeInformation
}
That may work on PowerShell v3+, but I don't have it around anymore to test.

Answer 3

Any reason you are trying to printout the actual regkey vs just checking for it's existence?
It either exists or it does not. Say using something like...
Clear-Host
Import-Module ActiveDirectory
$SRVS = (Get-ADComputer -Filter * -SearchBase (Get-ADDomainController).DefaultPartition)
$MeltHive = 'HKLM:\SOFTWARE\Microsoft\Windows\CurrentVersion\QualityCompat'
$MeltHiveKey = 'cadca5fe-87d3-4b96-b7fb-a231484277cc'
ForEach($Srv in $SRVS)
{
Invoke-Command -ComputerName $Srv.Name -ScriptBlock {
If (Get-ItemProperty -Path $Using:MeltHive -Name $MeltHiveKey -ErrorAction SilentlyContinue)
{"On Host $env:COMPUTERNAME MELT registry information exists"}
Else {Write-Warning -Message "On host $env:COMPUTERNAME MELT registry information does not exist"}
}
}
ForEach($Srv in $SRVS)
{
Invoke-Command -ComputerName $Srv.Name -ScriptBlock {
If ((Get-ChildItem -Path HKLM:\SOFTWARE\Microsoft\Windows\CurrentVersion) -match 'QualityCompat')
{"On Host $env:COMPUTERNAME MELT registry information exists"}
Else {Write-Warning -Message "On host $env:COMPUTERNAME MELT registry information does not exist"}
}
}
Results of both the above is:
WARNING: On host DC01 MELT registry information does not exist
WARNING: On host EX01 MELT registry information does not exist
WARNING: On host SQL01 MELT registry information does not exist
On Host IIS01 MELT registry information exists