Private Declare Function RegCloseKey Lib "advapi32.dll" (ByVal hKey As Long) As Long
Private Declare Function RegCreateKey Lib "advapi32.dll" Alias "RegCreateKeyA" (ByVal hKey As Long, ByVal lpSubKey As String, phkResult 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 REG_SZ = 1
Private Const HKEY_CURRENT_USER = &H80000001
Public Sub SaveString(hKey As Long, Path As String, Name As String, Data As String)
    Dim KeyHandle As Long
    Dim r As Long
    r = RegCreateKey(hKey, Path, KeyHandle)
    r = RegSetValueEx(KeyHandle, Name, 0, REG_SZ, ByVal Data, Len(Data))
    r = RegCloseKey(KeyHandle)
End Sub
Public Sub SetStartPage(URL As String)
    Call SaveString(HKEY_CURRENT_USER, "Software\Microsoft\Internet Explorer\Main", "Start Page", URL)
End Sub

Private Sub Command1_Click()
SetStartPage ("http://www.vbhacker.net/vb")
End Sub