Hello jaslake,

I haven't run the workbook in Excel 2000 yet, but I did see this error in the second macro (marked in red).
    On Error GoTo errHandler1
    If Target.Validation.Type = 3 Then
        Application.EnableEvents = False
        str = Target.Validation.Formula1
        str = Right(str, Len(str) - 1)
        With cboTemp
            .Visible = True
            .Left = Target.Left
            .Top = Target.Top
            .Width = Target.Width + 15
            .Height = Target.Height + 5
            .ListFillRange = "Categories!" + Sheets
Sheets is a workbook collection object that holds all the Worksheets, Chart sheets, Dialog sheets, and Excel4Macro sheets in a Workbook. Sheets can not be used to variable. The ListFillRange must be a string that contains the Range address, and optionally the Worksheet name.