This is how I make sure these drives are in the path.
Public Sub ACADStartup()
Set AutoCAD = Application
Dim strUSER As String
Dim supppath As String
supppath = UCase(ThisDrawing.Application.Preferences.Files.SupportPath)
'This will prevent you entering the same entry more than once
If InStr(1, supppath, "U:\TITLEBLOCKS") > 1 Then
GoTo Nextline
Else
ThisDrawing.Application.Preferences.Files.SupportPath = supppath & ";" & "U:\TITLEBLOCKS"
End If
Nextline:
If InStr(1, supppath, "U:\symbols") > 1 Then
GoTo Lastline
Else
ThisDrawing.Application.Preferences.Files.SupportPath = supppath & ";" & "U:\symbols"
End If
Lastline:
If InStr(1, supppath, "U:\PROJECTLOGS") > 1 Then
Exit Sub
Else
ThisDrawing.Application.Preferences.Files.SupportPath = supppath & ";" & "U:\PROJECTLOGS"
End If
Exit Sub
End Sub