Runtime error 91 in Excel/VBA on assigning Workbook variable

Question

I have this code in Creator workbook and I am copying data from the data file I select. But the code gives me the following error:

Object variable or with block variable not set

Sub transfer()
Dim myfile As Workbook
Dim myWs As Worksheet
Dim DataWs As Worksheet

Set myWs = ThisWorkbook.ActiveSheet

myfile = Application.GetOpenFilename(, , "Browse For Data file")
Workbooks.Open myfile
Set DataWs = myfile.Sheets("Instru Input")

myWs.Range("C3:C11000").Copy
DataWs.Range("E2").PasteSpecial xlPasteAll
myWs.Range("E3:E11000").Copy
DataWs.Range("F2").PasteSpecial xlPasteAll
myWs.Range("G3:G11000").Copy
DataWs.Range("G2").PasteSpecial xlPasteAll
myWs.Range("I3:I11000").Copy
DataWs.Range("H2").PasteSpecial xlPasteAll
myWs.Range("K3:K11000").Copy
DataWs.Range("I2").PasteSpecial xlPasteAll
myWs.Range("M3:M11000").Copy
DataWs.Range("J2").PasteSpecial xlPasteAll
myWs.Range("O3:O11000").Copy


ThisWorkbook.SaveAs

ThisWorkbook.Close

End Sub

Answer 1

This is what GetOpenFileName does by the specification from here :

Displays the standard Open dialog box and gets a file name from the user without actually opening any files.

Thus, once you get the file name (with the file path) as a string, it should be recorded as a string. Using this string, a workbook variable could be assigned with Set myWb = Workbooks.Open(fileName) :

Sub TestMe()

    Dim fileName As String
    fileName = Application.GetOpenFilename(, , "Browse For Data file")
    Debug.Print fileName

    Dim myWb As Workbook
    Set myWb = Workbooks.Open(fileName)

End Sub

In general, this is how a working code, taking some info from one worksheet to a worksheet in another workbook would look like:

Sub TestMe()

    Dim fileName As String
    fileName = Application.GetOpenFilename(Title:="Browse For Data file")
    Debug.Print fileName

    Dim targetWs As Worksheet
    Set targetWs = Workbooks.Open(fileName).Worksheets("Instru Input")

    Dim sourceWs As Worksheet
    'To avoid using the ActiveSheet:
    Set sourceWs = ThisWorkbook.Worksheets("NameOfTheWorksheet") 

    With sourceWs
        .Range("C3:C11000").Copy targetWs.Range("E2")
        .Range("E3:E11000").Copy targetWs.Range("F2")
        'And so on ...
    End With

    ThisWorkbook.SaveAs "WriteFileAddressHere.xlsb"
    ThisWorkbook.Close

End Sub

Make sure that you change "NameOfTheWorksheet" string and "WriteFileAddressHere.xlsb" to something relevant.