File extension funny - no extension

If I run this code, I get a file and it has the correct data in it, but the file does NOT have the given extension .SCF . Tried on Win7 and Win10, and it had me a bit flummoxed. Does anyone else get this? Is that a reserved extension of some sort? ( Not serious though as I just used another extension without problem ).

  Dim f as folderitem
  Dim b as binarystream
  Dim x as string
  
  f=GetFolderItem("test.SCF")
  if f=nil then return
  if f.exists then f.delete
  x=f.name
  
  b=BinaryStream.Create(f)
  If b=nil then return
  b.Write x
  b.close

Do you have the Windows Explorer option “Hide extensions for known file types” turned on?

No. I always show all file extensions.

Same here. But when I click on the file’s properties, it says it is: Windows Explorer Command, so it might reserved. I Googled, others mention the hidden extension as well.

Thanks Merv. Probably a scripting file extension. Thanks for verifying the issue, and your time.