Programmatically updating network printer drivers - powershell

Question

this is a deployment issue I'm hoping to solve with some simple Powershell:
When doing 32 bit Windows XP to 64 Bit Windows 7 migration, USMT is
migrating all the network printers, which is great. As the drivers
are obviously not correct though, the driver needs to be manually
upgraded (right click printer --> Update Driver).
Is there a WMI function or Powershell cmdlet for this action? I cant seem to find any
documentation on it! As our USMT task sequence is separate from the
deployment and runs under the migrated user's context I'm sure it
would work. If I could just get the right syntax, add a Powershell
script at the end of the TS that would be perfect.
I'm basically looking for the function that would have the same result as right-clicking the printer and clicking 'Update Driver'. I've cross posted here from the MDT forums as I think this would probably be more appropriate!
I've looked at Win32_Printer class but doesn't look like it has what I need.

Answer 1

How I understand it, doing a RC-> Update Driver is not really the correct way to manage print drivers.
Update driver is designed to update a driver from Version X to the next Version Y and not really the correct way to change the driver from a Win XP driver to a Win 7 driver (i.e. if the XP driver is at version 1.0, and the Win 7 driver is at 1.0, then running Update driver will not do anything because the versions will be the same).
The #1 and best option is to use PowerShell remove the printers, and re-add them (which will then also install the Windows 7 drivers). That way you will guarantee that they will work.
The script will be something like this:
#Get list of all the printers on the machine
$printers = gwmi win32_printer
#Save default Printer
$DefaultPrinter = $printers | where{$_.Default} | Select ShareName
#Create a list of all the printers we want to delete (in this case I am deleting all network printers)
$PrintersToDelete = $printers | where{$_.Network -eq $true}
#Create a list of all the printers we want to add (in this case, all network printers I just deleted)
$PrintersToAdd = $printers | where{$_.Network -eq $true} | Select Name
#Delete the printers I want to delete
$PrintersToDelete | foreach{$_.delete()}
#Add back all printers we want to add
$PrintersToAdd | foreach{(New-Object -ComObject WScript.Network).AddWindowsPrinterConnection($_.Name)}
#Get list of all the new printers on the machine
$printers = gwmi win32_printer
#Set the default printer
$NewDefaultPrinter = $printers | where{$_.DeviceID -match $DefaultPrinter}
$NewDefaultPrinter.SetDefaultPrinter()