Back to Basics: Use PowerShell to Search Servers for Specific Software

An old acquaintance, Mr. Rupert Torquil-Smythe Esq. (yes, it is he), recently wanted to know whether a certain piece of software was installed on a particular list of servers in his test lab.

I asked him for the list of servers (servers.txt) and the name of the software (Python). I then wrote and ran this:

$Servers = Get-Content -Path .\servers.txt

foreach ($Server in $Servers) {

$Found = (Get-WmiObject -ComputerName $Server -Query {select name from win32_product where name like '%Python%'} -ErrorAction SilentlyContinue).Name

if ($Found) {

Add-Content -Path .\output.txt -Value "================"

Add-Content -Path .\output.txt -Value "$Server"

Add-Content -Path .\output.txt -Value "================"

foreach ($Entry in $Found) {

Add-Content -Path .\output.txt -Value $Entry

}

Add-Content -Path .\output.txt -Value " "

}

}

 

We end up with a text file (output.txt) containing details of each server that has Python installed.

Things to note:

• servers.txt is read and stored as a variable ( $Servers)
• we use WMI to query each of the remote servers, from  $Servers, in a foreach loop
• the query string is WQL
  • we only ask for the name property to be returned (select name is more efficient than select * )
  • % allows for a wildcard search, e.g. any number of characters before and after Python
• Win32reg_AddRemovePrograms rather than Win32_Product should be used in production environments

Comments

• Anonymous
  March 25, 2016
  has ms changed its opinion on win32_product, previously they'd mention to not use it in production. Don't really remember the issue.
• Anonymous
  March 25, 2016
  cool stuff
  thanks
  
• Anonymous
  March 26, 2016
  @tony - Thank you... and I believe you are referring to this: https://support.microsoft.com/en-gb/kb/974524
  
  The work-around (Win32reg_AddRemovePrograms) involves having an SCCM agent installed, so won't be an option for everyone. Even on Windows Server 2012 R2, Win32_Product will produce the described behaviour (re-evaluation and potential repair), so use with caution!
  
  My esteemed friend, of course, only has servers in a test lab :)
  
  
• Anonymous
  March 26, 2016
  a
• Anonymous
  August 05, 2016
  A very handy script for a windows system administrator, thanks for sharing.
• Anonymous
  September 06, 2017
  The Win32reg_AddRemovePrograms class does not have a 'Name" property. It only has a "DisplayName' so you would have to edit the query like so:$Found = (Get-WmiObject -Query {select DisplayName from win32reg_AddRemovePrograms where DisplayName like '%Microsoft%'} -ErrorAction SilentlyContinue).DisplayName