Merging of excel files which has 10 sheets in each

Sub ImportDistricts()
'Instructional Message Box
MsgBox "Click OK to acess explorer." & vbCrLf & _
"Navigate to the folder path that contains" & vbCrLf & _
"the District workbooks you want to import." & vbCrLf & vbCrLf & _
"When you get inside that folder path," & vbCrLf & _
"use your mouse to select one workbook," & vbCrLf & _
"or use the Ctrl button with your mouse" & vbCrLf & _
"to select as many District workbooks" & vbCrLf & _
"as you want from that same folder path." & vbCrLf & vbCrLf & _
"There is a limit of one path per macro run," & vbCrLf & _
"but as many workbooks per path as you want." & vbCrLf & vbCrLf & _
"Please click OK to get started.", 64, "Instructions..."
'Variable declarations
Dim Tlr As Long, Alr As Long, u As String, v As String, w As Worksheet, x As Integer, y As Integer, z As Variant
z = Application.GetOpenFilename(FileFilter:="Excel files (*.xls), *.xls", MultiSelect:=True)
'Prepare Excel
With Application
.ScreenUpdating = False
.EnableEvents = False
End With
'Open loop for action to be taken on all selected workbooks.
On Error Resume Next
For x = 1 To UBound(z)
'Error handler within code if Cancel is clicked in Open dialog.
If Err.Number = 13 Then
With Application
.ScreenUpdating = True
.EnableEvents = True
End With
MsgBox "You did not select any workbooks." & vbCrLf & _
"Click OK to exit this macro.", 48, "Import action cancelled."
On Error GoTo 0
Err.Clear
Exit Sub
End If
'Open the workbook(s) that were selected.
Workbooks.Open (z(x))
'Open loop to act on every sheet.
For Each w In ActiveWorkbook.Worksheets
'Identify sheet name
v = w.Name
'Determine if the sheet name in the District workbook also exists in the Main workbook.
'If not, create one in the Main workbook. If so, disregard and move on.
Err.Clear
On Error Resume Next
u = ThisWorkbook.Worksheets(v).Name
If Err.Number <> 0 Then
With ThisWorkbook
.Worksheets.Add(After:=.Sheets(.Sheets.Count)).Name = v
End With
End If
On Error GoTo 0
Err.Clear
'At this point we know there is a sheet name in the Main workbook
'for every sheet name in the District workbook, which will remain unique, not duplicated.
'Determine the next available row in the Main workbook for this particular sheet in the District workbook.
'If structures are to guard against run time error if sheet(s) is / are blank.
If Application.CountA(w.Cells) <> 0 Then
On Error Resume Next
Alr = w.Cells.Find(What:="*", After:=[A1], SearchOrder:=xlByRows, SearchDirection:=xlPrevious).Row
On Error GoTo 0
Else
Alr = 1
End If
If Application.CountA(ThisWorkbook.Worksheets(v).Cells) <> 0 Then
Tlr = ThisWorkbook.Worksheets(v).Cells.Find(What:="*", After:=[A1], SearchOrder:=xlByRows, SearchDirection:=xlPrevious).Row + 1
Else
Tlr = 1
End If
'Copy the rows from the District sheet to the Main workbook's sheet whose name is the same.
w.Rows("1:" & Alr).Copy ThisWorkbook.Worksheets(v).Cells(Tlr, 1)
'Continue and terminate the loop for all worksheets in the District workbook.
Next w
'Close the District workbook without saving it.
ActiveWorkbook.Close False
'Continue and terminate the loop for the selected District workbooks.
Next x
'Restore Excel.
With Application
.ScreenUpdating = True
.EnableEvents = True
End With
'Message box to inform user the job is complete.
MsgBox "The import is complete.", 64, "Done !!"
End Sub

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