Sub ブックの読み取り専用の切替2()
    With ActiveWorkbook
        If .ReadOnly Then
            .ChangeFileAccess Mode:=xlReadWrite
        Else
            .ChangeFileAccess Mode:=xlReadOnly
        End If
    End With
End Sub

 Dim wb As Workbook

Set wb = Workbooks.Open(fpath, , , , , , 1) '書き込みでブックを開く

Public Const NET As String = "\\個人フォルダ\13_金属相場\相場\"

Sub Ni書込()

Dim r As Range

Dim myFile As String

Dim Nendo As String

Dim シート名 As String

Dim 検索日 As String

Dim wb As Workbook

    Nendo = Year(Date)

    myFile = "Ni相場" & Nendo & ".xls"

    シート名 = ThisWorkbook.Sheets("まとめ").Range("P21").Value

    検索日 = ThisWorkbook.Sheets("まとめ").Range("Q21").Value

 fpath = NET & "LME Ni相場\" & myFile

' Set wb = Workbooks.Open(fpath)

     Set wb = Workbooks.Open(fpath, , , , , , 1) '書き込みでブックを開く

    Dim myRange As Range

    Dim myObj As Range

    Dim keyWord As String

    Set myRange = Range("A4:A26")

    wb.Activate

    Set myObj = myRange.Find(検索日, LookAt:=xlWhole)

    If myObj Is Nothing Then

        MsgBox "'" & myFile & 検索日 & "'はありませんでした"

    Else

'        MsgBox "'" & keyWord & "'は" & myObj.Row & "行目にあります"

'    ActiveWorkbook.ChangeFileAccess Mode:=xlReadWrite   '★書き込み切り替え

        wb.Sheets(シート名).Range("B" & myObj.Row).Value = Workbooks("金属相場更新ファイルver2.xlsm").Worksheets("まとめ").Range("N21").Value

        wb.Sheets(シート名).Range("D" & myObj.Row - 1).Value = Workbooks("金属相場更新ファイルver2.xlsm").Worksheets("まとめ").Range("N22").Value

wb.Save

wb.ChangeFileAccess Mode:=xlReadOnly  '★読み込み切り替え

wb.Close

    End If

   Set myObj = Nothing

   Set myRange = Nothing

End Sub