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Private Declare Function getUserName Lib "advapi32.dll" Alias "GetUserNameA" (ByVal lpBuffer As String, nSize As Long) As Long

Private Sub Form_Load()
Dim myUserName AS String

myUserName = UserName()
End Sub

Private Function UserName() As String
Dim User As String
Dim retcode As Long

User = String(255, " ")
retcode = getUserName(User, Len(User))
UserName = Left(User, Len(Trim(User)) - 1)
End Function