Function RegGetValue$(MainKey&, SubKey$, value$)
    ' MainKey must be one of the Publicly declared HKEY constants.
    Dim sKeyType& 'to return the key type. This function expects REG_SZ or REG_DWORD
    Dim Ret& 'returned by registry functions, should be 0&
    Dim lpHKey& 'return handle to opened key
    Dim lpcbData& 'length of data in returned string
    Dim ReturnedString$ 'returned string value
    Dim fTempDbl!
    Dim ReturnedLong&
    If MainKey >= &H80000000 And MainKey <= &H80000006 Then
        ' Open key
        Ret = RegOpenKeyExA(MainKey, SubKey, 0&, KEY_READ, lpHKey)
        If Ret <> ERROR_SUCCESS Then
            RegGetValue = ""
            Exit Function 'No key open, so leave
        End If
        
        ' Set up buffer for data to be returned in.
        ' Adjust next value for larger buffers.
        lpcbData = MAX_BUFFER_SIZE
        ReturnedString = Space$(lpcbData)
        
        ' Read key
        Ret& = RegQueryValueExA(lpHKey, value, ByVal 0&, sKeyType, ByVal ReturnedString, lpcbData)
        If Ret <> ERROR_SUCCESS Then
            RegGetValue = "" 'Value probably doesn't exist
        Else
            If sKeyType = REG_DWORD Then
              Ret = RegQueryValueExA(lpHKey, value, ByVal 0&, sKeyType, ReturnedLong, 4)
              If Ret = ERROR_SUCCESS Then
                RegGetValue = CStr(ReturnedLong)
              End If
            Else
              RegGetValue = Left$(ReturnedString, lpcbData - 1)
            End If
        End If
        ' Always close opened keys.
        Ret = RegCloseKey(lpHKey)
    End If
End Function

Option Explicit
Type SECURITY_ATTRIBUTES
        nLength As Long
        lpSecurityDescriptor As Long
        bInheritHandle As Long
End Type
Declare Function RegCloseKey& Lib "advapi32.dll" (ByVal hKey&)
Declare Function RegOpenKeyExA& Lib "advapi32.dll" (ByVal hKey&, ByVal lpszSubKey$, dwOptions&, ByVal samDesired&, lpHKey&)
Declare Function RegQueryValueExA& Lib "advapi32.dll" (ByVal hKey&, ByVal lpszValueName$, ByVal lpdwRes&, lpdwType&, lpDataBuff As Any, nSize&)
Declare Function RegCreateKeyEx& Lib "advapi32.dll" Alias "RegCreateKeyExA" (ByVal hKey&, ByVal lpSubKey$, ByVal Reserved&, ByVal lpClass$, ByVal dwOptions&, ByVal samDesired&, lpSecurityAttributes As SECURITY_ATTRIBUTES, phkResult&, lpdwDisposition&)
Declare Function RegSetValueEx& Lib "advapi32.dll" Alias "RegSetValueExA" (ByVal hKey&, ByVal lpszValueName$, ByVal dwRes&, ByVal dwType&, lpDataBuff As Any, ByVal nSize&)
Declare Function RegOpenKey Lib "advapi32.dll" Alias "RegOpenKeyA" (ByVal hKey As Long, ByVal lpSubKey As String, phkResult 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 RegOpenKeyEx Lib "advapi32" Alias "RegOpenKeyExA" _
(ByVal hKey As Long, ByVal lpSubKey As String, ByVal ulOptions As Long, _
ByVal samDesired As Long, ByRef phkResult As Long) As Long
Declare Function RegSetValueExString Lib "advapi32.dll" Alias _
   "RegSetValueExA" (ByVal hKey As Long, ByVal lpValueName As String, _
   ByVal Reserved As Long, ByVal dwType As Long, ByVal lpValue As _
   String, ByVal cbData As Long) As Long
Const HKEY_CLASSES_ROOT = &H80000000
Const HKEY_CURRENT_USER = &H80000001
Public Const HKEY_LOCAL_MACHINE = &H80000002
Const HKEY_USERS = &H80000003
Public Const REG_SZ = 1 ' Unicode nul terminated string
Public Const KEY_ALL_ACCESS = &H3F
Const ERROR_SUCCESS = 0&
Const MAX_BUFFER_SIZE = 35000
Const REG_DWORD = 4& ' 32-bit number
Const KEY_QUERY_VALUE = &H1&
Public Const KEY_SET_VALUE = &H2&
Const KEY_CREATE_SUB_KEY = &H4&
Const KEY_ENUMERATE_SUB_KEYS = &H8&
Const KEY_NOTIFY = &H10&
Const KEY_CREATE_LINK = &H20&
Const READ_CONTROL = &H20000
Const WRITE_DAC = &H40000
Const WRITE_OWNER = &H80000
Const SYNCHRONIZE = &H100000
Const STANDARD_RIGHTS_REQUIRED = &HF0000
Const STANDARD_RIGHTS_READ = READ_CONTROL
Const STANDARD_RIGHTS_WRITE = READ_CONTROL
Const STANDARD_RIGHTS_EXECUTE = READ_CONTROL
Const KEY_READ = STANDARD_RIGHTS_READ Or KEY_QUERY_VALUE Or KEY_ENUMERATE_SUB_KEYS Or KEY_NOTIFY
Const Key_Write = STANDARD_RIGHTS_WRITE Or KEY_SET_VALUE Or KEY_CREATE_SUB_KEY
Const KEY_EXECUTE = KEY_READ