Macro Error - First Sheet In Each File To Master File

I am receiving an error at

Set CopyRng = Wkb.worksheet1.Range(Cells(RowofCopyworksheet, 1),
Cells(Cells(Rows.Count, 1).End(xlUp).Row, Cells(1, Columns.Count).End(xlToLeft).Column))

I am trying to copy the first sheet in each file in the designated folder and paste it into a master worksheet.

Below is the code.

'Description: Combines all files in a specific folder to Format File for Upload.xls
Sub MergeMultipleFiles()
Dim path As String, ThisWB As String, lngFilecounter As Long
Dim wbDest As Workbook, shtDest As Worksheet, ws As Worksheet
Dim filename As String, Wkb As Workbook
Dim CopyRng As Range, Dest As Range
Dim RowofCopySheet As Integer

[Code] ....