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Sub EXCEL_FORMAT_HM_BS(FileNm As String)
    Dim oApp            As Object                 '　Application Object
    Dim oWkb            As Object                 '　Excel.Workbook Object
    Dim oWsh            As Object                 '　Excel.WorkSheet Object
    Dim MaxRow          As Long
    Dim MaxCol          As Long
    Dim MaxCol_A        As String
    Dim rng             As Range
    
    On Error GoTo ErrProc

    Set oApp = CreateObject("Excel.Application")
    Set oWkb = oApp.Workbooks.Open(FileNm)
    Set oWsh = oWkb.Worksheets(1)           '1シート目を対象

    'oApp.Visible = True

    oWsh.Activate

    With oWsh

        MaxRow = .Cells(oWsh.Rows.Count, 1).End(xlUp).Row                                   '最終行
        MaxCol = .Cells(1, oWsh.Columns.Count).End(xlToLeft).Column                         '最終列 数字
        MaxCol_A = .Cells(1, MaxCol).Address(RowAbsolute:=True, ColumnAbsolute:=False)      '最終列 アドレス取得
        MaxCol_A = Left(MaxCol_A, InStr(MaxCol_A, "$") - 1)                                 '最終列のアルファベットだけを取得
        
         '空白セルを選択して、色を付ける。
         Set rng = .Range("A1:" & MaxCol_A & MaxRow).SpecialCells(xlCellTypeBlanks)
         With rng.Interior
            .Pattern = xlSolid
            .PatternColorIndex = xlAutomatic
            .ThemeColor = xlThemeColorDark1
            .TintAndShade = -0.149998474074526
            .PatternTintAndShade = 0
        End With
 
    End With

    oWkb.Close saveChanges:=True

Proc_EXIT:
    oApp.Quit

    Set oApp = Nothing
    Set oWkb = Nothing
    Set oWsh = Nothing

    DoCmd.SetWarnings 1
    Exit Sub
ErrProc:
    MsgBox Err.Number & " " & Err.Description
    Resume Proc_EXIT
End Sub