Internet Explorer VBScript Issue - launches two instances of IE on laptops, only one on desktops

Hi all,

I am currently utilising a VB Script in Active Directory to launch Internet Explorer automatically when a user logs in. Strangely, this works perfectly for all desktop machines, but not for laptops (where two instances of IE open). The machines are grouped in two different AD OU's.

I initially thought that this might be due to differing IE versions, but I have tested and this is not the case.

Any help would be greatly appreciated, VBScript below:

Set objExplorer = CreateObject("InternetExplorer.Application")
objExplorer.Navigate "URL"
objExplorer.Visible = true
objExplorer.ToolBar = false
objExplorer.MenuBar = false
objExplorer.StatusBar = false
objExplorer.AddressBar = false
objExplorer.Left = 0
objExplorer.Top = 0

Thanks!