Question

I have a block of code that opens and closes a registry key to find a piece of information that determines the user’s location so that it can select the appropriate filepath when openeing a data file. It works fine in Windows XP with Office 2002 and 2007, but doesn’t work in 32 or 64 bit versions of Windows 7 with Excel 2010.
Can anyone tell me what I need to change to get this working?

'\* Module Level Constant Declarations follow...
Private Const cvarRegistrySize = 1
Private Const cvarHkeyLocalMachine = &H80000002
Private Const cvarKeyQueryValue = &H2

'\* Private API Function Declarations follow...
Declare PtrSafe Function RegOpenKeyEx Lib "advapi32.dll" Alias "RegOpenKeyExA" ( _
ByVal hKey As LongPtr, ByVal lpSubKey As String, ByVal ulOptions As Long, _
    ByVal samDesired As Long, phkResult As LongPtr) As Long
Declare PtrSafe Function RegQueryValueEx Lib "advapi32.dll" Alias "RegQueryValueExA" ( _
ByVal hKey As LongPtr, ByVal lpValueName As String, ByVal lpReserved As LongPtr, _
lpType As Long, lpData As Any, lpcbData As Long) As Long               
Declare PtrSafe Function RegCloseKey Lib "advapi32.dll" (ByVal hKey As LongPtr) As Long

'\* Dimension variables at module level...
Private strSearchKey    As String
Private strRegion       As String
Private intCharLen      As Integer
Private intSubChar      As Integer
Private lngRegKey       As Long
Private lngSizeVar      As Long
Private lngReturnCode   As Long
'****************************************************************************
'* Function to extract the current region from the registry                 *
'****************************************************************************
Function GETREGION() As String
'\* registry key for user's location...
strSearchKey = "SOFTWARE\CompanyName\LogonProcess"
'\* open registry key...
lngReturnCode = RegOpenKeyEx(cvarHkeyLocalMachine, strSearchKey, 0, cvarKeyQueryValue, lngRegKey) 'returns 2
'\* return value from specified key...
strSearchKey = "CurrentLocation"
'\* return section of string from specified key...
strRegion = String(20, 32)
'\* returns the length of the string...
lngSizeVar = Len(strRegion) - 1
'\* query the registry key...
lngReturnCode = RegQueryValueEx(lngRegKey, strSearchKey, 0, cvarRegistrySize, ByVal strRegion, lngSizeVar) 'returns 6
'\* close the registry key...
    Call RegCloseKey(lngRegKey)
'\* select the location from the string...
lngReturnCode = GETSTR(GETREGION, strRegion, 1, vbNullChar)
'\* return result to function as uppercase...
    GETREGION = StrConv(GETREGION, vbUpperCase)
End Function

'****************************************************************************
'* Function to extract a section from a string from a given start position  *
'* up to a specified character.                                             *
'****************************************************************************
Function GETSTR(strX As String, strY As String, intStartPos As Integer, intSearchChar As String) As Integer
'\* initialisation of variables follows...
GETSTR = intStartPos
strX = ""
intCharLen = Len(strY)
intSubChar = intStartPos
'\* if comparison character at start position then leave function with empty extracted string...                                                      *
    If Mid(strY, intStartPos, 1) = intSearchChar Then Exit Function
'\* begin loop...
        Do
'\* create integer value based on character positions...
            strX = strX + Mid(strY, intSubChar, 1)
'\* increment counter...
                intSubChar = intSubChar + 1
'\* if counter exceeds string length, exit loop...
                    If intSubChar > intCharLen Then Exit Do
'\* define loop conditions...
        Loop Until Mid(strY, intSubChar, 1) = intSearchChar
'\* return character position to function...
GETSTR = intSubChar
End Function

It is becoming critical that I resolve this as it may hold back the roll-out of our new desktop image as this code is used in a function which is part of an Excel add-in which is deployed to all the machines and used by a large number of associates.
The return codes from RegOpenKeyEx and RegQueryValueEx of 2 and 6 respectively are what are throwing me.
Thanks in advance
Martin

Answer 1

The error codes indicate

(0x000002) The system cannot find the file specified.
(0x000006) The handle is invalid

You pass cvarKeyQueryValue = &H2 as the samDesired rights request which is KEY_SET_VALUE (0x0002) – on windows 7 without elevation this write request to HKLM will be denied.

Try opening the key with KEY_READ (0x20019) instead as you only need to read the value.