The following will retrieve the logged-on user to the current machine:

Option Explicit

Public Declare Function GetComputerName Lib "kernel32" Alias
"GetComputerNameA" _
  (ByVal lpBuffer As String, nSize As Long) As Long

Public Declare Function GetUserName Lib "advapi32.dll" _
  Alias "GetUserNameA" (ByVal lpBuffer As String, nSize As Long) As Long


Private Sub Command1_Click()

  Dim UserName As String
  Dim ComputerName As String

  GetUserInfo UserName, ComputerName
  
  Text1 = UserName
  Text2 = ComputerName
  
End Sub


Private Sub GetUserInfo(UserName, ComputerName)

  Dim r&, ret$
 
 'get the user's name
  ret$ = Space$(256)
  r& = GetUserName(ret$, Len(ret$))
  UserName = StripNull$(ret$)
  
 'get the computers's name
  ret$ = Space$(256)
  r& = GetComputerName(ret$, Len(ret$))
  ComputerName = StripNull$(ret$)

End Sub