excel macro run time error '1004'- Application defined or object defined error

Hi,

My requirement is to write a VBA code in Excel 2010 to merge the multiple excel files into one master excel file. I have written the below code-

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Sub Combine_Multiple_Excel_Files()
    Set wb = ThisWorkbook
    
    InitialFoldr$ = ThisWorkbook.Path & "\"    '<<< Startup folder to begin searching from
    With Application.FileDialog(msoFileDialogFolderPicker)
        .InitialFileName = Application.DefaultFilePath & "\"
        .Title = "Please select the files folder"
        .InitialFileName = InitialFoldr$
        .Show
        
        If .SelectedItems.Count <> 0 Then
            xDirect$ = .SelectedItems(1) & "\"
            xFname$ = Dir(xDirect$, 7)
            Do While xFname$ <> ""
            
                Workbooks.Open (xDirect$ & xFname$), UpdateLinks:=False
                
                Application.Workbooks(xFname$).Activate
                Set srcwb = Workbooks(xFname$)
    
                For Each sh In srcwb.Sheets
                    LR1 = wb.Sheets(1).Cells(Rows.Count, 3).End(xlUp).Row
                    LR2 = sh.Cells(Rows.Count, 1).End(xlUp).Row
                    wb.Sheets(1).Range("A" & LR1 & ":A" & (LR1 + LR2 - 4)).Value = (xDirect$ & xFname$)
                    wb.Sheets(1).Range("B" & LR1 & ":B" & (LR1 + LR2 - 4)).Value = sh.Name
                    sh.Range("A4:R" & LR2).Copy Destination:=wb.Sheets(1).Range("C" & LR1)
                Next
                
                Application.CutCopyMode = False 'Clear Clipboard
                srcwb.Close savechanges:=False
                xFname$ = Dir
                
            Loop
        End If
    End With
    
    Application.GoTo reference:=wb.Sheets(1).[A1]
    
End Sub
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However, when i run this macro, i receive the following error-

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excel macro run time error 1004

Application defined or object defined error

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When i press Debug, i see that the error is coming at-

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wb.Sheets(1).Range("A" & LR1 & ":A" & (LR1 + LR2 - 4)).Value = (xDirect$ & xFname$)

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I am new to VBA programming. So, Can anyone please help me here? This is urgent.

Thanks,
Karan