删除重复值时出现Excel VBA错误。运行时出错，但单步执行时出错

Question

我得到＆＃34;运行时错误＆＃39; 1004＆＃39;：应用程序定义或对象定义错误＆＃34;当命中Run Sub（F5）时运行整个子程序。但是，当我使用调试功能（F8）逐步执行它时，它会无误地传递此行。有什么我可以在代码中更改以纠正此问题。代码如下：

lastrow = Sheet9.Cells(Rows.count, 1).End(xlUp).Row
Range(Sheet9.Cells(1, 1), Sheet9.Cells(lastrow, 14)).Clear
lastrow = Sheet3.Cells(Rows.count, ProjCol).End(xlUp).Row
For i = 1 To lastrow
    Sheet3.Range(Sheet3.Cells(i + 1, ProjCol), Sheet3.Cells(i + 1, LampCol)).Copy Destination:=Sheet9.Range(Sheet9.Cells(i, 1), Sheet9.Cells(i, 2))
Next i
lastrow2 = Sheet9.Cells(Rows.count, 1).End(xlUp).Row

'ERROR OCCURS WITH LINE BELOW
Sheet9.Range(Cells(1, 1), Cells(lastrow2, 2)).RemoveDuplicates Columns:=Array(1, 2), Header:=xlNo