Jim,
Thanks for the tip. I think I tried it correctly but I still get the same error. Here is more or less what I am attempting, just to try to get something simple to work:

Basically, I need to create a modeless .net form from a VFP app. The modeless form is actually a MDIparent. I need to respond to a couple of events from this form; one to refresh the VFP form when the user performs a certain function and one to tell the VFP app that the user has closed the .Net form. So I create the .NEt form with code like the following:

x=CREATEOBJECT("testfoxclass2.frmshell")
frmShell=x.ReturnForm
(the return form method returns the .net form object. I have also tried creating a separate thread using this method, but same results)

frmshell.show
(The .net form is displayed OK.)

Next I execute a .prg that sets the eventhandler as follows:

oEvents = NEWOBJECT("myclass")
zz = EVENTHANDLER(frmShell, oEvents)
RETURN
DEFINE CLASS myclass AS session OLEPUBLIC

IMPLEMENTS IJEEvents IN "c:\documents and settings\thompssj\my documents\visual studio projects\testfoxclass2\bin\testfoxclass2.tlb"

PROCEDURE IJEEvents_ShellClosed() AS VOID
frmshell = .NULL.
RELEASE frmshell
PUBLIC frmshell
ENDPROC

PROCEDURE IJEEvents_ButtonClicked() AS VOID
MESSAGEBOX(".net form button clicked")
ENDPROC

ENDDEFINE

I put the code: RAiseEvent ShellClosed() in the .net form_closed method. Have also tried putting it in the form_closing method.

When I close the .net form, the event is fired correctly and I release the VFP form object.

I then put the call to your Closer method after the READEVENTS of my simple VFP tester app:
x.closer

I release all the objects again before the VFP app quits.

Still get this goofy error.

Thanks for helping. I'm about to give up and use a little VB6 dll to raise the events between my .net dll and VFP. This works without any issues.