I'm attempting to store a variable for reference when different workbooks
open. I'm aware of the following options

Hidden names: I believe this to be an undocumented/unsupported feature
which may be unstable or no longer available in future releases. (Are there
"non-hidden" names?)

Excel worksheet cell (hidden worksheet, hidden workbook, personal.xls, etc.)

Add-in: Not really sure of advantages/disadvantages?

INI file:

I would actually prefer to used the INI file if not only because other
applications could access the information. I was under the impression that
an INI file was simply a text file. I opened c:\windows\win.ini and it did
appear to be a simple text file of variables and their values. However, the
following code retrieved a variable and it's value that doesn't appear to be
in the INI file? Any ideas what happens if you try to retrieve a value from
an INI file that doesn't exist. For example, if I provide a co-worker with
the .xls file but forget to provide them with the INI file what happens when
the code runs?

Private Declare Function GetPrivateProfileString _
Lib "kernel32" Alias "GetPrivateProfileStringA" _
(ByVal lpApplicationName As String, ByVal lpKeyName As String, _
ByVal lpDefault As String, ByVal lpReturnedString As String, _
ByVal nSize As Long, ByVal lpFileName As String) As Long

Private Sub readFromINI()
Dim sFileName As String, sHeader As String, sKey As String
Dim buf As String * 256
Dim length As Long


sFileName = "C:\WINDOWS\WIN.INI"
sHeader = "intl"
sKey = "sCountry"

length = GetPrivateProfileString( _
sHeader, sKey, "<no value", _
buf, Len(buf), sFileName)
MsgBox Left$(buf, length)
End Sub

Thanks in advance,

Christmas May