For many years I have used scripts of my own design to build workstations and to roll out software updates. At the time I created these I found that most of the tools which could accomplish these tasks were unwieldy. Group Policy software deployment in particular never really seemed fit for purpose since it extended login times so dramatically. My experience gained in a previous job spent packaging applications for deployment had taught me that all installed software populates consistent information in the Windows Registry, so in my current job I tended to audit this data directly via my scripts. This was saved into an SQL database from where it could be queried, or manipulated via a data source in Excel.

I’m working my notice period at the moment ready for a new job I’ll start in October, and so I’m going over the stuff I have created in the current job in order to prepare my handover documents. Mindful of the dependency my current employer has on these custom scripts I decided to get a quote for a Dell KACE solution, thinking that since it’s a Virtual Appliance, and since there are only 150 PCs here it shouldn’t be too expensive – after all it’s only really providing what my scripts already do (workstation builds, drivers, software deployment, and auditing). But here’s the thing – they wanted something like £13,000! (I can’t recall the precise figure). To put it in context this figure is around one third of the cost of replacing all the workstations with new ones, or say half the annual salary of an IT support technician – quite out of the question.

Unsurprisingly I have decided instead to simply tidy up my scripts to make them easier to use. Sure, you could accomplish these tasks with SCCM but that’s not free either. In an SME, why spend huge amounts of money on something that can be automated without much trouble using mechanisms that are built in. Heck, even the uninstall command line is stored in the registry for virtually all software – that’s how the Add/Remove Programs Control Panel works! And most software can be installed silently in the desired way provided you research the command line arguments to do so. It’s no accident that AppDeploy.com which was a great crowdsourced repository of this knowledge became KACE which was then acquired by Dell. It still exists, though the content doesn’t seem to be as well maintained as it was.

I have used a startup script written in VBScript to keep software up to date on workstations. A startup script runs as the SYSTEM account so permissions are not an issue. Since I also maintain an unattended installation I already have a package folder with all the scripts to install each package. All I needed to code was a way to audit the Registry for each package and add some logic around that. Up until now, I had tended to write sections of the script specifically tailored for each package, and from there it’s not much of a stretch to apply packages to a workstation based on its OS version, or Active Directory OU or group membership. For the script I have published below, I have recreated this logic as a single function which can be invoked with a one line entry for each package (see the highlighted part) – everything else is taken care of. I hope it helps someone to save £13,000 :)

Sample script output

Running software package check for Adobe Flash Player...
  Registry data found at branch "Adobe Flash Player ActiveX"
  Comparing detected version 11.3.300.271 against desired version 11.4.402.265
  Removing old version 11.3.300.271
    Killing iexplore.exe
    Override detected, running "u:\packages\flash\uninstall_flash_player.exe -uninstall"
    u:\packages\flash\uninstall_flash_player.exe -uninstall
  Installing Adobe Flash Player 11.4.402.265

Running software package check for Paint.NET...
  Registry data found at branch "{529125EF-E3AC-4B74-97E6-F688A7C0F1C0}"
  Comparing detected version 3.60.0 against desired version 3.60.0
  Paint.NET is already installed and up to date.

Running software package check for Adobe Reader...
  Registry data found at branch "{AC76BA86-7AD7-1033-7B44-AA0000000001}"
  Comparing detected version 10.0.0 against desired version 10.1.4
  Removing old version 10.0.0
    Using UninstallString from the Registry, plus "/qb-!"
    MsiExec.exe /I{AC76BA86-7AD7-1033-7B44-AA0000000001} /qb-!
  Installing Adobe Reader 10.1.4

Running software package check for Photo Gallery...
  Registry data found at branch "{60A1253C-2D51-4166-95C2-52E9CF4F8D64}"
  Comparing detected version 16.4.3503.0728 against desired version 16.4.3503.0728
  Photo Gallery is already installed and up to date.

Running software package check for Mendeley Desktop...
  Installing Mendeley Desktop 1.6

The script

'startup.vbs
'patters 2006-2012

Option Explicit
Dim objNetwork, objShell, objReg, strKey, colProcess, objProcess, arrSubKeys 
Dim strFileServer
Const HKEY_CURRENT_USER = &H80000001
Const HKEY_LOCAL_MACHINE = &H80000002

'set up objects
Set objNetwork = CreateObject("WScript.Network")
Set objShell = CreateObject("WScript.Shell")
Set objReg = GetObject("winmgmts:{impersonationLevel=impersonate}!\\.\root\default:StdRegProv")

strFileServer = "YOURSERVERHERE"
MapNetworkDrive "U:","unattended"

Package "flash.cmd", "Adobe Flash Player", "11.4.402.265", "u:\packages\flash\uninstall_flash_player.exe -uninstall", False, True, "iexplore.exe"    
Package "paintnet.cmd", "Paint.NET", "3.60.0", "/qb-!", False, False, "" 
Package "adobe.cmd", "Adobe Reader", "10.1.4","/qb-!",False, False, array("outlook.exe","iexplore")
Package "photogal.cmd", "Photo Gallery", "16.4.3503.0728", "/qb-!", False, False, "iexplore.exe"
Package "mendeley.cmd", "Mendeley Desktop", "1.6", "/S", True, False, "winword.exe"

objNetwork.RemoveNetworkDrive "U:", True, True
WScript.Echo VbCrLf & "Finished software checks"


Function Package(strPackageName, strTargetDisplayName, strTargetVersion, strExtraUninstParams, boolExtraUninstQuotes, boolUninstForceOverride, ProcessToKill)

  '=============================================================================

  'To understand this function you need to know that installed software packages
  'will populate keys below these branches of the Registry:
  '  HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall
  '  HKLM\SOFTWARE\Wow6432Node\Microsoft\Windows\CurrentVersion\Uninstall
  '    (the latter for 32bit software on 64bit Windows)
  'This is the data that is mined when you look at Add/Remove Programs
  'in the Control Panel 

  'strPackageName is the package script on your package server (e.g. flash.cmd)

  'strTargetDisplayName can be a full or partial match of the Registry key
  'DisplayName (matches from the left)
  '  "Java(TM)" would match "Java(TM) 6 Update 5" and all other versions

  'strTargetVersion is the full version number from DisplayVersion in the Registry
  'Each decimal point of precision will be compared in turn.

  'If the Registry key DisplayVersion is not used by a package, the same number
  'of digits is parsed from the right hand side of the DisplayName string

  'strExtraUninstParams is used when you want to override the command line
  'specified by QuietUninstallString in the Registry, or for when that value is
  'missing for example, sometimes InnoSetup packages will specify the switch
  '/SILENT in QuietUninstallString, but you may need to override by appending
  '/VERYSILENT to the command line in UninstallString
  'If neither QuietUninstallString and UninstallString are present, the script
  'will use strExtraUninstParams as the full uninstall command line
  
  'Some packages define UninstallString as a long filename but forget to
  'surround it with quotes. You can correct this by setting
  'boolExtraUninstQuotes = True
  '   Package "mendeley.cmd", "Mendeley Desktop", "1.6", "/S", True, False, "winword.exe"

  'In some cases you may want to ignore the value of both QuietUninstallString
  'and UninstallString and override the command completely. To do this, set
  'boolUninstForceOverride to True
  '   Package "flash.cmd", "Adobe Flash Player", "11.4.402.265", "u:\packages\flash\uninstall_flash_player.exe -uninstall", False, True, "iexplore.exe"

  'Finally, ProcessToKill is a string or array containing the name(s) of any
  'running process(es) you need to kill, if plugins are being installed for Word
  'or Internet Explorer for instance.

  '=============================================================================

  Dim arrBranches, strBranch, boolRemoval, strActualDisplayName, strActualVersion
  Dim strQuietUninstall, strUninstall
  WScript.Echo VbCrLf & "Running software package check for " & strTargetDisplayName & "..."
  'we need to iterate through both the 32 and 64bit uninstall branches of the Registry
  arrBranches = Array("SOFTWARE\Wow6432Node\Microsoft\Windows\CurrentVersion\Uninstall\", "SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\")
  For Each strBranch In arrBranches
    'firstly, remove old version of package if it's present
    objReg.EnumKey HKEY_LOCAL_MACHINE, strBranch, arrSubKeys
    If IsArray(arrSubkeys) Then
      For Each strKey in arrSubkeys
        objReg.GetStringValue HKEY_LOCAL_MACHINE, strBranch & strKey, "DisplayName", strActualDisplayName
        If Left(strActualDisplayName, Len(strTargetDisplayName)) = strTargetDisplayName Then
          'we've found the target software package
          WScript.Echo "  Registry data found at branch """ & strKey & """"
          'is there a version string (not all software will have one)?
          objReg.GetStringValue HKEY_LOCAL_MACHINE, strBranch & strKey, "DisplayVersion", strActualVersion
          If Not IsNull(strActualVersion) Then
          Else
            'if there's no version string we'll try to grab the same number of chars from the right hand side of the DisplayName string  
            strActualVersion = Right(strActualDisplayName, Len(strTargetVersion))
          End If
          If (IsUpgradeNeeded (strActualVersion,strTargetVersion)) = True Then
            strQuietUninstall = ""
            WScript.Echo "  Removing old version " & strActualVersion
            KillProcess ProcessToKill
            'check the package's registry settings
            objReg.GetStringValue HKEY_LOCAL_MACHINE, strBranch & strKey, "UninstallString", strUninstall
            objReg.GetStringValue HKEY_LOCAL_MACHINE, strBranch & strKey, "QuietUninstallString", strQuietUninstall
            If Not strExtraUninstParams = "" Then
              'Extra parameters were sent to the function
              If boolUninstForceOverride = True Then
                'Entire uninstall command line was forced so use strExtraUninstParams, regardless of what's in the Registry
                WScript.Echo "    Override detected, running """ & strExtraUninstParams & """"
                WScript.Echo "    " & strExtraUninstParams
                WinExec strExtraUninstParams
              ElseIf Not IsNull(strUninstall) Then
                'use the basic UninstallString plus the additional parameters
                If boolExtraUninstQuotes = True Then
                  strUninstall = """" & strUninstall & """"
                End If
                strUninstall = strUninstall & " " & strExtraUninstParams
                WScript.Echo "    Using UninstallString from the Registry, plus """ & strExtraUninstParams & """"
                WScript.Echo "    " & strUninstall
                WinExec strUninstall
              Else
                'no UninstallString was found in the Registry, so assume that strExtraUninstParams is the full removal command line
                WScript.Echo "    No UninstallString found, running """ & strExtraUninstParams & """"
                WScript.Echo "    " & strExtraUninstParams
                WinExec strExtraUninstParams
              End If
            Else
              'No extra parameters were sent to the function
              'if there's already a value for QuietUninstallString then use that command line
              If Not IsNull(strQuietUninstall) Then
                WScript.Echo "    Using QuietUninstallString directly from the Registry"
                WScript.Echo "    " & strQuietUninstall
                WinExec strQuietUninstall
              ElseIf Not IsNull(strUninstall) Then
                'no QuietUninstallString was found, fall back to UninstallString
                If boolExtraUninstQuotes = True Then
                  strUninstall = """" & strUninstall & """"
                End If
                WScript.Echo "    Using UninstallString directly from the Registry"
                WScript.Echo "    " & strUninstall
                WinExec strUninstall
              Else
                WScript.Echo "    ERROR - this package doesn't seem to have any UninstallString defined - you'll need to send one to the Package function (see script source for details)"
                Exit Function
              End If
            End If
          Else
            'IsUpgradeNeeded (strActualVersion,strTargetVersion) is False
            'package was detected, but version is >= than the one specified
            WScript.Echo "  " & strTargetDisplayName & " is already installed and up to date."
            Exit Function
          End If
        End If
      Next
    End If
  Next
  'install package
  WScript.Echo "  Installing " & strTargetDisplayName & " " & strTargetVersion
  KillProcess ProcessToKill
  WinExec "U:\packages\" & strPackageName
End Function


Function IsUpgradeNeeded(strVerActual,strVerDesired)
  Dim arrActualVersion, arrDesiredVersion, i
  'Break software version down on decimal points
  arrActualVersion = split(strVerActual,".")
  arrDesiredVersion = split(strVerDesired,".")
  WScript.Echo "  Comparing detected version " & strVerActual & " against desired version " & strVerDesired
  'iterate, comparing each sub-version number starting from left
  For i = 0 To UBound(arrActualVersion)
    'WScript.Echo "  comparing digit... is " & arrActualVersion(i) & " less than " & arrDesiredVersion(i) 
    If arrActualVersion(i) < arrDesiredVersion(i) Then
      'installed version is out of date
      IsUpgradeNeeded = True
      Exit Function
    ElseIf arrActualVersion(i) > arrDesiredVersion(i) Then
      'installed version is newer
      IsUpgradeNeeded = False
      Exit Function     
    End If
  Next
  'thus far the version numbers are the same, but there may be additional
  'decimal points of precision in the desired version
  '  e.g. Adobe Reader 10.1.4 is newer than 10.1
  If UBound(arrDesiredVersion) > UBound(arrActualVersion) Then
    IsUpgradeNeeded = True
  Else
    IsUpgradeNeeded = False
  End If
End Function


Function MapNetworkDrive(strDriveLetter, strSharePath)
  On Error Resume Next
  'if the share name is not a UNC path, assume it's on the normal fileserver
  If Not Left(strSharePath,2) = "\\" Then
    strSharePath = "\\" & strFileServer & "\" & strSharePath
  End If
  If objFSO.DriveExists(strDriveLetter) Then
    objNetwork.RemoveNetworkDrive strDriveLetter, True, True
  End If
  objNetwork.MapNetworkDrive strDriveLetter, strSharePath
  If Err.Number <> 0 Then
    WScript.Echo "Error - " & Err.Description
    Err.Clear
  End If
  On Error Goto 0
End Function


Function WinExec(strExec)
  Dim objExec, eTime
  WinExec = True
  Set objExec = objShell.Exec(strExec)
  eTime = DateAdd("s", 120, Now)
  Do While objExec.Status = 0
    WScript.Sleep 1000
  Loop
End Function


Function KillProcess(Process)
  Dim strProcessElement
  If IsArray(Process) Then
    For Each strProcessElement in Process
      KillIndividualProcess(strProcessElement)
    Next
  ElseIf Not Process = "" Then
    KillIndividualProcess(Process)
  End If
End Function


Function KillIndividualProcess(strProcess)
  Dim colProcess, objProcess
  Set colProcess = objWMI.ExecQuery("Select * from Win32_Process")
  For Each objProcess in colProcess
    If LCase(objProcess.Name) = LCase(strProcess) Then
      WScript.Echo "    Killing " & strProcess
      'occasionally one parent process may kill all children leading to an object error
      'so disable error handling temporarily
      On Error Resume Next
      objProcess.Terminate()
      On Error Goto 0
    End If
  Next
End Function