To create a drop-down control with a list of used or unused drive letters, place two ComboBox controls on a form, named Combo1 and Combo2, and include this code to initialize the lists:
Private Declare Function GetLogicalDrives Lib _"kernel32" () As LongPrivate Sub Form_Load()FillCombo Combo1, TrueFillCombo Combo2, FalseEnd SubPrivate Sub FillCombo(cbo As ComboBox, _ByVal bUsed As Boolean)Dim DriveNum As Longcbo.ClearFor DriveNum = 0 To 25If CBool(GetLogicalDrives And (2 ^ _DriveNum)) = bUsed Thencbo.AddItem Chr$(Asc("A") + _DriveNum) & ":"End IfNext DriveNumEnd Sub
