PowerShell create a new object and add the values to an array - powershell

Question

What I am trying to achieve here is add the servers and the updates that are not installed on the server to an array and create a new object that is going to display the names of the servers in one column and the missing updates on another column, but at the end I am getting an empty Grid-View table.
The values for the servers and updates are read from a file.
Write-Host
#Read the password from stdin and store it in a variable
$password = Read-Host -AsSecureString -Prompt "Enter your password"
Write-Host
#Get credentials and password for later user
$cred = New-Object System.Management.Automation.PSCredential ("Administrator#testing.local", $password )
#Get the list of available servers to test
$servers = Get-Content -Path $HOME\Desktop\servers.txt
#Get the list of available updates that need to be installed on the server
$available_updates = Get-Content $HOME\Desktop\update.txt
$add_updates = #()
$add_updates_and_servers = #()
#Get each server name from the list and execute the following commands
foreach ($server in $servers) {
#Test if the server is reponding
$ping = Test-Connection $server -Count 1 -Quiet
#If the above command returns True continue
if ($ping -eq "True") {
#Write a message saying Testing server_name
Write-Host "Testing $server"
foreach ($update in $available_updates) {
#Check if update is installed
$updates_from_os = Invoke-Command -ComputerName $server -Credential $cred -ScriptBlock { Get-HotFix | Select-Object -Property HotFixID | Where-Object -Property HotFixID -EQ $Using:update } -HideComputerName | Select-Object -ExpandProperty HotFixID
if (!$updates_from_os) {
$add_updates += $update
}
}
New-Object -TypeName PSObject -Property $updates -OutVariable final
$updates = #{
"Server" = $server
"Updates" = $add_updates
}
}
$add_updates_and_servers += $final
}
$add_updates_and_servers | Out-GridView

Answer 1

For what is probably happening with your script:
I suspect that each time you calling the statement New-Object -TypeName PSObject -Property $updates -OutVariable final You overwriting any previous created $final object which references to the same objects as your $add_updates_and_servers collection.
Anyways, try to avoid using the increase assignment operator (+=) to create a collection, instead stream the results to a variable (or even better, directly to next/final cmdlet: ... }| Out-GridView).
Something like:
$add_updates_and_servers = foreach ($server in $servers) {
$ping = Test-Connection $server -Count 1 -Quiet
if ($ping -eq "True") {
Write-Host "Testing $server"
$add_updates = #(
foreach ($update in $available_updates) {
$updates_from_os = Invoke-Command -ComputerName $server -Credential $cred -ScriptBlock { Get-HotFix | Select-Object -Property HotFixID | Where-Object -Property HotFixID -EQ $Using:update } -HideComputerName | Select-Object -ExpandProperty HotFixID
if (!$updates_from_os) { $update }
}
)
[PSCustomObject]#{
"Server" = $server
"Updates" = $add_updates
}
}
}
Note: in case you want each $update in a separate column, also have a look at: Not all properties displayed