Ensure single class instance but with multiple references to it

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I have written a class module which creates a link to an ActiveX server
and provides some functions. Because the server doesn't seem to be
able to handle multiple references being set to it I am trying to
ensure that only one instance of my class is created and that all other
attempts to create a new instance merely set a pointer to the existing
instance. To do this I have the following in a standard module:

Private m_clsOpenServer As cOpenServer

Public Function GetOpenServer() As cOpenServer
If m_clsOpenServer Is Nothing Then
Set m_clsOpenServer = New cOpenServer
End If
Set GetOpenServer = m_clsOpenServer
End Function


I then reference the class by:
Dim clsOpenServer As cOpenServer
Set clsOpenServer = GetOpenServer

When I'm finished I destroy the object, ie.
Set clsOpenServer = Nothing

Now comes the problem. Even though clsOpenServer is destroyed,
m_clsOpenServer remains in memory and so there is still a reference to
my class object and to the ActiveX server.


I thought the thing to do here was to add a terminate procedure:
Public Sub TerminateOpenServer()
Set m_clsOpenServer = Nothing
End Sub
and then call this after clsOpenServer is set to nothing. If there
were other pointers set to m_clsOpenServer then I thought it would be
held in memory even though I set it to nothing. This is not the case
however (not sure why not??) and so the next time I call GetOpenServer
a new instance is created (and then pretty soon the application I am
calling freezes up).

Is there any robust way to handle this type of situation?

Thanks a lot,
Andrew

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