Excel copy from file to file macro not working - vba

Question

I have to copy data from multiple excel files named with numbers (1.xlsx, 2.xlsx, 3.xlsx, etc). I wrote this macro. It runs. But no copy happens, the main workbook in which I ran the macro remains empty.
Sub filecopy()
' The macro is running in the main file, which I saved as .xlsm
' This main.xlsm is in the same folder as the files from which I copy the data
Dim Filename As String, Pathname As String,xx as Double
Activesheet.Usedrange.Clear 'I delete the current contents of the sheet
Pathname = ActiveWorkbook.Path
Filename = Dir(Pathname & "*.xlsx")
xx = 1 'the first column where the contents of the first file goes
Do While Len(Filename) > 0
Cells(1, xx).Formula = "='[" & Filename & "]Sheet1'!A1"
Cells(2, xx).Formula = "='[" & Filename & "]Sheet1'!B2"
Cells(3, xx).Formula = "='[" & Filename & "]Sheet1'!C3"
xx = xx + 1 'next file next column
Filename = Dir()
Loop
ActiveSheet.UsedRange.Value = ActiveSheet.UsedRange.Value 'every formula goes to value
MsgBox "Work Complete", vbInformation
End Sub

Answer 1

There are 2 errors in your code:
1. \ is missing -> filename is empty
Replace Filename = Dir(Pathname & "*.xlsx") with Filename = Dir(Pathname & "\*.xlsx")
2. the formula is not correct -> not complete filename
Change your formulas e.g. Cells(1, xx).Formula = "='[" & Filename & "]Sheet1'!A1" with this Cells(1, xx).Formula = "='" & Pathname & "\[" & Filename & "]Sheet1'!A1"

Answer 2

What about a solution like this:
Pathname = ActiveWorkbook.Path 'Be sure is the rigth path
Filename = Dir(Pathname & "\*.xlsx") 'I've addedd a "\"
xx = 1
Do While Len(Filename) > 0
If Filename <> ThisWorkbook.Name Then
Set mFile = Workbooks.Open(Pathname & "\" & Filename)
Else
GoTo NextFile
End If
With mFile.ActiveSheet 'Use the sheet you need here
Cells(1, xx) = .Cells(1, 1).Value
Cells(2, xx) = .Cells(2, 1).Value
Cells(3, xx) = .Cells(3, 1).Value
End With
xx = xx + 1 'next file next column
Application.DisplayAlerts = False
mFile.Close savechanges:=False
Application.DisplayAlerts = True
Set mFile = Nothing
NextFile:
Filename = Dir()
Loop