Dim swApp As SldWorks.SldWorks
Dim swModel As SldWorks.ModelDoc2
Dim boolstatus As Boolean
Dim IErrors As Long
Dim IWarnings As Long
Dim folderFullPath As String
Dim ConfNameArr As Variant
Dim ConfigName As String

Sub main()

Set swApp = Application.SldWorks
Set swModel = swApp.ActiveDoc

' check is .SLDPRT is opened
If swModel Is Nothing Then
    MsgBox "[ERROR] No active files found!"
    Exit Sub
End If

' check is active document is .SLDPRT file
If swModel.GetType <> swDocPART Then
    MsgBox "[ERROR] Open .SLDPRT first!"
    Exit Sub
End If

' zooms to fit the model in the graphics area.
swModel.ViewZoomtofit2

' saves the model.
boolstatus = swModel.Save3(swSaveAsOptions_Silent, IErrors, IWarnings)

FilePath = swModel.GetPathName ' Get the full path of the part/assembly file
FileTitle = swModel.GetTitle   ' Get the full part name

PathSize = Strings.Len(FilePath)    ' Get the length of the full path
TitleSize = Strings.Len(FileTitle)  ' Get the length of the part name
FolderSize = Strings.Len(FilePath) - Strings.Len(FileTitle) ' Get the length of the folder

RootFolderName = Strings.Left(FilePath, FolderSize)     ' Truncate to folder name

MfFolderPath = RootFolderName & "3mf\"
StlFolderPath = RootFolderName & "stl\"
StepFolderPath = RootFolderName & "step\"

'checking existing of 3mf, step, stl folders
If Dir(MfFolderPath) = "" Then
    'MsgBox "[ERROR] Folders '3mf', 'step', 'stl' not found!"
    MfFolderPath = RootFolderName
    StlFolderPath = RootFolderName
    StepFolderPath = RootFolderName
    'Exit Sub
End If

FileName = Strings.Left(FileTitle, Len(FileTitle) - 7)

ConfNameArr = swModel.GetConfigurationNames
For i = 0 To UBound(ConfNameArr)
    ConfigName = ConfNameArr(i)
    swModel.ShowConfiguration2 (ConfigName)
    MfFilePath = MfFolderPath & FileName & "_" & ConfigName & ".3mf"
    StlFilePath = StlFolderPath & FileName & "_" & ConfigName & ".stl"
    StepFilePath = StepFolderPath & FileName & "_" & ConfigName & ".step"
    boolstatus = swModel.SaveAs3(MfFilePath, 0, 2)
    boolstatus = swModel.SaveAs3(StlFilePath, 0, 2)
    boolstatus = swModel.SaveAs3(StepFilePath, 0, 2)
Next i

MsgBox ("3MF, STEP and STL saved!")

'close the document
'swApp.CloseDoc FileTitle

' errors
Debug.Print ("Errors as defined in swFileSaveError_e: " & IErrors)

' warnings
Debug.Print ("Warnings as defined in swFileSaveWarning_e: " & IWarnings)

End Sub