Copy Paste Cells To Newly Created Workbook

My code in the first workbook generates a new workbook with a variable in the filename, then copies the cells from the first workbook to the newly created workbook. This code is working properly when used in a draft worksheet I use for testing. As soon as I put it in the master file, an error message pops up "Runtime error 1004 : select method of range class failed". Then the debug sends me to the line " Cells.Select ". What should I be looking for, why does my code work on one file but when i put it in another one it doesn't ?

Private Sub CommandButton1_Click()
Dim line_counter As Long
Dim prm_line_value As Boolean
prm_line_value = False
Do
prm_line_value = Sheets("Rate").Cells(1 + line_counter, 1).Value
line_counter = line_counter + 1
Loop Until prm_line_value = False
line_counter = line_counter - 1
Dim Wk As Workbook
Dim number_of_new_wb_needed As Integer
If line_counter < 5000 Then.....................