Disable Remove Option on Virtual Project Node in VSIS app

I am not able to disable Remove Option on Virtual Project Node in VSIS app.  I have tried the IDelete interfaces, Node CanDelete and below code.  Nothing seems to work.

It gets removed from the Node, however I can still see Remove option on Edit menu.

Please let me know if you have any idea.

protected override int QueryStatusOnNode(Guid cmdGroup, uint cmd, IntPtr pCmdText, ref QueryStatusResult result)        {            if (cmdGroup == VsMenus.guidStandardCommandSet97)            {                switch ((VSConstants.VSStd97CmdID)cmd)                {                    case VSConstants.VSStd97CmdID.Cut:                    case VSConstants.VSStd97CmdID.Delete:                    case VSConstants.VSStd97CmdID.Remove:                    case VSConstants.VSStd97CmdID.Copy:                        result = QueryStatusResult.SUPPORTED | QueryStatusResult.INVISIBLE;                        return VSConstants.S_OK;                    case VSConstants.VSStd97CmdID.Open:                    case VSConstants.VSStd97CmdID.OpenProjectItem:                        result = QueryStatusResult.ENABLED | QueryStatusResult.SUPPORTED;                        return VSConstants.S_OK;                          default:                        result = QueryStatusResult.SUPPORTED | QueryStatusResult.INVISIBLE;                        return VSConstants.S_OK;                    }            }            return base.QueryStatusOnNode(cmdGroup, cmd, pCmdText, ref result);        }