Windows Tip Sheet
What Software's in Your Box?
Hard to believe, but even scripting has its weaknesses -- particularly if you need a list of all your computer's installed software.
A reader on ScriptingAnswers.com asked why the WMI Win32_Product class doesn't seem to list every installed software product on Windows machines. Here's a sample script, which should work on WinXP, you can run to see what I'm talking about:
On Error Resume Next
strComputer = "."
UserName = ""
Password = ""
Set SWBemlocator = CreateObject("WbemScripting.SWbemLocator")
Set objWMIService = SWBemlocator.ConnectServer
Set colItems = objWMIService.ExecQuery("Select *
For Each objItem in colItems
WScript.Echo "Caption: " & objItem.Caption
WScript.Echo "Description: " & objItem.Description
WScript.Echo "IdentifyingNumber: " &
WScript.Echo "InstallDate: " & objItem.InstallDate
WScript.Echo "InstallDate2: " & objItem.InstallDate2
WScript.Echo "InstallLocation: " & objItem.InstallLocation
WScript.Echo "InstallState: " & objItem.InstallState
WScript.Echo "Name: " & objItem.Name
WScript.Echo "PackageCache: " & objItem.PackageCache
WScript.Echo "SKUNumber: " & objItem.SKUNumber
WScript.Echo "Vendor: " & objItem.Vendor
WScript.Echo "Version: " & objItem.Version
If you run this and compare it to what's in Add/Remove Programs, you'll likely spot things in the GUI that the script doesn't list. So what gives? The problem is that, even in this day and age, software applications exist which don't use the Windows Installer service to install themselves. Win32_Product really only asks Windows Installer to give up the list of what's installed; if Windows Installer didn't install something, then it doesn't know about it, and so the script doesn't detect it. There's unfortunately nothing you can do about this except to bug vendors to repackage their software to use Windows Installer.
Don Jones is a multiple-year recipient of Microsoft’s MVP Award, and is an Author/Evangelist for video training company Pluralsight. Don is also a co-founder and President of PowerShell.org, a community dedicated to Microsoft’s Windows PowerShell technology. Don has more than two decades of experience in the IT industry, and specializes in the Microsoft business technology platform. He’s the author of more than 50 technology books, an accomplished IT journalist, and a sought-after speaker and instructor at conferences worldwide. Reach Don on Twitter at @concentratedDon, or on Facebook at Facebook.com/ConcentratedDon.