I can offer you a partial solution. This code will map  a drive  if it
can. The error portion of the code you can attempt a different drive,
or whatever.

Sub Map()
On Error GoTo MapError

Set Map = CreateObject("WScript.Network")
Map.MapNetworkDrive "F:", "\\server\folder", , "UserName", "Password"

Set Map = Nothing

MapError:
MsgBox ("F is connected already")

End Sub


I'm not  sure how to verify password/username accuracy.