This short snippet of code will return the parent directory of a directory input, or the directory of a filename input.

s = "C:\test drive\yeah\boo.htm"
i = InStrRev(s, "\")
s = Left(s, i)
MsgBox s

If the input is a directory (C:\Windows\System) it will return that directory's parent (C:\Windows\). If the input is a file (C:\Windows\System\icon.jpg) it will return that file's directory (C:\Windows\System\).