Memory problem with macro in Excel: How do I solve this problem?

Question

I have a problem with a macro in Excel. Here the code. There are actually quite a few subs that are I am not reporting for a matter of space. However, the most important one is attached.

Sub randomdata_generator()
Application.ScreenUpdating = False
Application.DisplayAlerts = False


Dim FromProducts As Integer
Dim ToProducts As Integer
Dim StepProducts As Integer
Dim FromStations As Integer
Dim ToStations As Integer
Dim StepStations As Integer

FromProducts = Range("G1").Value
ToProducts = Range("I1").Value
StepProducts = Range("K1").Value
FromStations = Range("G2").Value
ToStations = Range("I2").Value
StepStations = Range("K2").Value

For h1 = FromProducts To ToProducts Step StepProducts
    For h2 = FromStations To ToStations Step StepStations
        Index = 0
        For xx1 = 1 To 17 Step 1 'NC
            x1 = h1
            x2 = h2
            Range("B1").Value = x1
            D = Application.WorksheetFunction.Round(x1 * 0.1, 0)
            E = Application.WorksheetFunction.Round(x1 * 0.2, 0)
            BAEG = Application.WorksheetFunction.Round(x1 * 0.35, 0)

            For xx2 = 1 To 5 Step 1
            If x2 >= x1 Then GoTo prossimo
                Range("B2").Value = x2
                Range("B4").Value = 20 * x2   'D

                For x3 = 1 To 5 'NI
                    Range("B3").Value = x3
                    If x3 > 1 Then
                        q = 3
                    Else
                        q = 1
                    End If
                    For g = 1 To q
                        x5 = 1
                        Range("B5").Value = x5                         

                        s = E
                        For i = 0 To s - 1
                            Range("A25").Offset(0, D + i).Value = 0.3
                            Range("A28").Offset(0, D + i).Value = 0.2
                            Range("A46").Offset(0, D + i).Value = 0.009 
                        Next

                    Next
               Next
            Next
        Next
    Next
Next

Application.DisplayAlerts = True
Application.ScreenUpdating = True
End Sub

This is the part of the code that saves the new file that has been generated.

Sub salvanuovo()
Application.ScreenUpdating = False
Application.DisplayAlerts = False
    Dim wbkCurrent As Workbook

    Index = Index + 1
    If Index Mod 200 = 0 Then
        newHour = Hour(Now())
        newMinute = Minute(Now()) + 1
        newSecond = Second(Now()) + 30
        waitTime = TimeSerial(newHour, newMinute, newSecond)
        Application.Wait waitTime
        DoEvents
    End If
    ActiveWorkbook.SaveCopyAs Filename:=ThisWorkbook.Path & "\Data\Dati(" & (x1 / 10) & "_" & (x2) & "_" & Index & ").xlsm" 'example: "C:\Users\lucag\Desktop\randomdata_generator_alternativa\Dati(" & Index & ").xlsm"
    Workbooks.Open Filename:=ThisWorkbook.Path & "\Data\Dati(" & (x1 / 10) & "_" & (x2) & "_" & Index & ").xlsm"
    Workbooks("Dati(" & (x1 / 10) & "_" & (x2) & "_" & Index & ").xlsm").Activate


    Sheets("Foglio1").Select                                                                                 
    ActiveWorkbook.SaveAs Filename:=ThisWorkbook.Path & "\Data\Dati(" & (x1 / 10) & "_" & (x2) & "_" & Index & ").xlsx", _
    FileFormat:=xlOpenXMLWorkbook, CreateBackup:=False
    Workbooks("Dati(" & (x1 / 10) & "_" & (x2) & "_" & Index & ").xlsx").Close
    Kill (ThisWorkbook.Path & "\Data\Dati(" & (x1 / 10) & "_" & (x2) & "_" & Index & ").xlsm")
    Set wbkCurrent = ActiveWorkbook
    wbkCurrent.Activate
    Set wbkCurrent = Nothing
End Sub

The following image shows the issue. The memory keeps loading until Excel crashes. Any hint on how to solve this problem. enter image description here

There is no .Copy nor .Paste just some .Value assigned

Selection.ClearContents
Range("A12").Select

Answer 1

The problem was related to the version of Excel. As soon as I move to a 64-bit version of Office 365 rather than the 32-bit version that I had before, everything was solved.

Answer 2

This is not a comprehensive answer, just somewhat of a start.

First, Excel VBA treats Integer types as Long internally. This answer shows more on that. So I would recommend using Long unless specific to backward compatibility for older Excel versions.

Next I see you are using worksheet functions. You don't need

D = Application.WorksheetFunction.Round(x1 * 0.1, 0)

as it can be reduced to

D = Round(x1 * 0.1, 0)

On top of that, you are accessing the worksheet an insane amount of times through the nested loops. It would be better, in my opinion, to limit the amount of times VBA must interact with ranges or worksheets to the minimum number of times, such as storing values into an array and dump the full array to the cells.

Additionally, you can look at this answer regarding memory problems as there are quite a few tips that may be applicable here.

And as a total side note, I would recommend using more meaningful variable names, especially when presenting to SO to help people determine what is going on.