I’ve encountered some applications that, during installation, change the default printer for the users on the machine, regardless if it’s installed from an admin account or system account.
To prevent this, you might want to look into the MSI custom actions, but if you don’t have that option, then these scripts can be a workaround.
First, we must create a backup script:
Set objRegistry = GetObject("winmgmts:\\.\root\default:StdRegProv")
Const HKEY_USERS = &H80000003
Const HKEY_LOCAL_MACHINE = &H80000002
Set WNetwork = CreateObject("WScript.Network")
strComputer = "."
Set objReg = GetObject("winmgmts:{impersonationLevel=impersonate}!\\" & strComputer & "\root\default:StdRegProv")
KEYPATH="Software\Microsoft\Windows NT\CurrentVersion\Windows"
VALUENAME="Device"
strUserName = WNetwork.username
If UCase(strUserName) = getUserNameFromSID("S-1-5-18") Then
string1 = "S-1-5-21"
string2 = "Classes"
objReg.EnumKey HKEY_USERS, "", arrsubkeys
For Each Subkey In arrSubKeys
If InStr(1,Subkey,string1,1)And (InStr(1,Subkey,string2,1) = "0") Then
ID = Subkey
strKeyPathSUB = ID & "\" & KEYPATH
objReg.GetStringValue HKEY_USERS,strKeyPathSUB,VALUENAME,strValue
if Not IsNull(strValue) then
strKeyPath = "SOFTWARE\DefaultPrinterBackup"
If objReg.EnumKey(HKEY_LOCAL_MACHINE, strKeyPath, arrSubKeys) <> 0 Then
objReg.CreateKey HKEY_LOCAL_MACHINE,strKeyPath
End If
strKeyPath1 = "SOFTWARE\DefaultPrinterBackup\" & ID
If objReg.EnumKey(HKEY_LOCAL_MACHINE, strKeyPath1, arrSubKeys) <> 0 Then
objReg.CreateKey HKEY_LOCAL_MACHINE,strKeyPath1
End If
strValueNameUsers = "Device"
objReg.SetStringValue HKEY_LOCAL_MACHINE,strKeyPath1,strValueNameUsers,strValue
end if
End If
Next
End If
Function getUserNameFromSID(SID)
server = "."
Set objWMIService = GetObject("winmgmts:\\" & server & "\root\cimv2")
Set objAccount = objWMIService.Get("Win32_SID.SID='" & SID & "'")
strUser = objAccount.AccountName
If Err.Number <> 0 Then
getUserNameFromSID = Err.Description
Err.Clear
Else
getUserNameFromSID = UCase(strUser)
End If
End Function
This script first checks if it’s executed from a system account, if this is run from an admin account then it fails.
The registry where the default printer is saved for a user can be found in “HKEY_CURRENT_USER\Software\Microsoft\Windows NT\CurrentVersion\Windows”, and the registry is “Device”
For example on my machine i have Device=Microsoft Print to PDF,winspool,Ne01:
We then search in all subkeys from “HKEY_USERS” except the ones that start with “Classes”, those are not users.
If we find the registry in the users hive, we then create a general key in “HKEY_LOCAL_MACHINE\Software\DefaultPrinterBackup”. We get each user key ID, for example “S-1-5-21-661462176-3111377266-2001793429-1001” and place the “Device” registry in it.
So now that we have the backup script done, we should create a restore one for all the users. This will look like this:
Set objRegistry = GetObject("winmgmts:\\.\root\default:StdRegProv")
Const HKEY_USERS = &H80000003
Const HKEY_LOCAL_MACHINE = &H80000002
Set WNetwork = CreateObject("WScript.Network")
strComputer = "."
Set objReg = GetObject("winmgmts:{impersonationLevel=impersonate}!\\" & strComputer & "\root\default:StdRegProv")
KEYPATH="Software\Microsoft\Windows NT\CurrentVersion\Windows"
VALUENAME="Device"
strUserName = WNetwork.username
strKeyPath = "SOFTWARE\DefaultPrinterBackup"
If strUserName = "SYSTEM" Then
string1 = "S-1-5-21"
string2 = "Classes"
objReg.EnumKey HKEY_USERS, "", arrsubkeys
For Each Subkey In arrSubKeys
If InStr(1,Subkey,string1,1)And (InStr(1,Subkey,string2,1) = "0") Then
ID = Subkey
strKeyPathSUB = ID & "\" & KEYPATH
objReg.GetStringValue HKEY_USERS,strKeyPathSUB,VALUENAME,strValue
strKeyPath1 = "SOFTWARE\DefaultPrinterBackup\" & ID
If objReg.EnumKey(HKEY_LOCAL_MACHINE, strKeyPath1, arrSubKeys) = 0 Then
objReg.GetStringValue HKEY_LOCAL_MACHINE,"SOFTWARE\DefaultPrinterBackup\" & ID,VALUENAME,strValuem
strv=strvaluem
objReg.DeleteValue HKEY_USERS,strKeyPathSUB,VALUENAME
objReg.SetStringValue HKEY_USERS,strKeyPathSUB,VALUENAME,strv
else
If objReg.EnumKey(HKEY_USERS, strKeyPathSUB, arrSubKeys) <> 0 Then
If objReg.EnumKey(HKEY_LOCAL_MACHINE, strKeyPath1, arrSubKeys) = 0 Then
objReg.GetStringValue HKEY_LOCAL_MACHINE,"SOFTWARE\DefaultPrinterBackup\" & ID,VALUENAME,strValuem
strv=strvaluem
objReg.SetStringValue HKEY_USERS,strKeyPathSUB,VALUENAME,strv
end if
end if
End If
If objReg.EnumKey(HKEY_USERS, strKeyPathSUB, arrSubKeys) = 0 Then
If objReg.EnumKey(HKEY_LOCAL_MACHINE, strKeyPath1, arrSubKeys) <> 0 Then
objReg.DeleteValue HKEY_USERS,strKeyPathSUB,VALUENAME
end if
end if
End If
Next
End If
If objReg.EnumKey(HKEY_LOCAL_MACHINE, strKeyPath, arrSubKeys) = 0 Then
objReg.DeleteKey HKEY_LOCAL_MACHINE,strKeyPath
end if
We are now doing the exact opposing. We are searching in the previously created key in “HKEY_LOCAL_MACHINE\Software\DefaultPrinterBackup\” and for each subkey, we copy it in the according user registry.
If you want to use these scripts in your MSI, place the backup script right after the “InstallInitialize” sequence, and the restore script before the “InstallFinalize” sequence.
