超出范围错误VBA

Question

我在Sheet1的A列中有一个值列表，并希望在工作簿中搜索值并返回选项卡名称（值将显示在多个选项卡中）。我正在使用此代码，但它一直给我一个“脚本超出范围错误”。任何人都可以解释一下发生了什么？

Sub Searchtab()
    Dim x, i As Long, WS As Worksheet, R As Range
    With Sheets("Sheet1").Cells(1).CurrentRegion
        .Columns(2).Offset(1).ClearContents
        x = .Value
        For Each WS In Worksheets
            If WS.Name <> "Sheet1" Then
                For i = 1 To UBound(x, 1)
                Set R = WS.Columns(1).Find(x(i, 1))
                    If Not R Is Nothing Then
                        x(i, 2) = x(i, 2) & IIf(x(i, 2) <> "", ", ", "") & WS.Name
                    End If
                Next
            End If
        Next
        .Resize(, 2).Value = x
    End With
End Sub

谢谢