Option Explicit
 
Private Type SECURITY_ATTRIBUTES
    nLength As Long
    lpSecurityDescriptor As Long
    bInheritHandle As Long
End Type
 
Private Declare Function RegCreateKeyEx Lib "advapi32.dll" Alias _
  "RegCreateKeyExA" (ByVal hKey As Long, ByVal lpSubKey As String, ByVal _
  Reserved As Long, ByVal lpClass As String, ByVal dwOptions As Long, ByVal _
  samDesired As Long, lpSecurityAttributes As SECURITY_ATTRIBUTES, phkResult As _
  Long, lpdwDisposition As Long) As Long
Private Declare Function RegCloseKey Lib "advapi32.dll" (ByVal hKey As Long) As _
Long
Private Declare Function RegSetValueEx Lib "advapi32.dll" Alias _
"RegSetValueExA" (ByVal hKey As Long, ByVal lpValueName As String, ByVal _
Reserved As Long, ByVal dwType As Long, lpData As Any, ByVal cbData As Long) As _
Long
Private Const STANDARD_RIGHTS_ALL = &H1F0000
Private Const SYNCHRONIZE = &H100000
Private Const HKEY_CLASSES_ROOT = &H80000000
Private Const REG_SZ = 1
Private Const STANDARD_RIGHTS_READ = &H20000
Private Const STANDARD_RIGHTS_WRITE = &H20000
Private Const REG_OPTION_NON_VOLATILE = 0
Private Const KEY_CREATE_LINK = &H20
Private Const KEY_CREATE_SUB_KEY = &H4
Private Const KEY_ENUMERATE_SUB_KEYS = &H8
Private Const KEY_QUERY_VALUE = &H1
Private Const KEY_NOTIFY = &H10
Private Const KEY_SET_VALUE = &H2
Private Const KEY_READ = ((STANDARD_RIGHTS_READ Or KEY_QUERY_VALUE Or _
  KEY_ENUMERATE_SUB_KEYS Or KEY_NOTIFY) And (Not SYNCHRONIZE))
Private Const KEY_EXECUTE = (KEY_READ)
Private Const KEY_WRITE = ((STANDARD_RIGHTS_WRITE Or KEY_SET_VALUE Or _
  KEY_CREATE_SUB_KEY) And (Not SYNCHRONIZE))
Private Const KEY_ALL_ACCESS = ((STANDARD_RIGHTS_ALL Or KEY_QUERY_VALUE Or _
KEY_SET_VALUE Or KEY_CREATE_SUB_KEY Or KEY_ENUMERATE_SUB_KEYS Or KEY_NOTIFY Or _
KEY_CREATE_LINK) And (Not SYNCHRONIZE))
 
Sub setupRegistry(myApp As String)
Dim key As Long
Dim sec_attrib As SECURITY_ATTRIBUTES
Dim disposition As Long
 
RegCreateKeyEx HKEY_CLASSES_ROOT, ".txt", 0, vbNullString, _
  REG_OPTION_NON_VOLATILE, KEY_ALL_ACCESS, sec_attrib, key, disposition
RegSetValueEx key, vbNullString, 0, REG_SZ, ByVal myApp, Len(myApp) + 1
RegCloseKey key
End Sub