Excel VBA运行时错误：溢出

Question

我一直在这个宏上出现溢出错误：

Sub searchAndCopy()

Dim wbOpen As Workbook
Set wbOpen = Workbooks("ExtractedColumns.xlsm")

Dim searchString As String
searchString = "-----------------------------------------------------------------"

Dim lastRow As Integer, i As Integer
lastRow = 0

Dim thisSheet As Worksheet
Set thisSheet = Sheets("Sheet1")

Dim sh As Worksheet

For i = thisSheet.Range("A" & Rows.Count).End(xlUp).Row To 1 Step -1
    If (thisSheet.Range("A" & i) = searchString) Then
        If lastRow = 0 Then
            lastRow = i
        Else
            Sheets.Add After:=Sheets(Sheets.Count)
            Set sh = ActiveSheet
            thisSheet.Rows(i + 1 & ":" & lastRow).Copy Destination:=sh.Rows("1:1")
            thisSheet.Rows(i + 1 & ":" & lastRow).Delete
            'Commenting the following code didn't affect the error, so I'm keeping them as comments until I figure it out
            'Call extractSiteColumns
            'For Each curr In ActiveSheet.UsedRange
                'If InStr(1, curr.Value, "----") > 0 Then curr.Value = ""
            'Next
            lastRow = i
        End If
    End If
Next i
End Sub

我几乎可以肯定导致错误的是在For循环开始之前的行中，因为for循环似乎没有执行（并且我没有更改任何内容）。我唯一想要修改的是对“ExtractedColumns”工作簿的引用。

有关导致此溢出错误的原因的任何想法？