Web App Crash, What does this Stack Log mean?

I’ve brought up that several of our apps crash and remain in memory. I’m starting to dive deep into investigating.

I have this in the Unhandled Exception for the session:

		Try
				dim log as string
				dim d as new date
				log = log + d.SQLDateTime + EndOfLine
				log = log + Error.Message + EndOfLine + error.Reason + join(error.stack, EndOfLine)
				
				'f= GetFolderItem("log.txt")
				Dim f As FolderItem = GetFolderItem("SessionErrorLog.txt")
				Dim t as TextOutputStream
				If f <> Nil then
						t = TextOutputStream.Append(f)
						t.WriteLine(log)
						t.Close
				End If 
				Return true
		Catch
				Return True
		end

And this is what came out:


WebSource.Append%%o<WebSource>si4b
WebLabel.Event_RenderHTML%o<WebSource>%o<WebLabel>
WebControl.Event_RenderHTML%o<WebSource>%o<WebControl>
WebObject._Render%o<WebSource>%o<WebObject>i4
WebContainer.Event_RenderHTML%o<WebSource>%o<WebContainer>
WebView.Event_RenderHTML%o<WebSource>%o<WebView>
WebControl.Event_RenderHTML%o<WebSource>%o<WebControl>
WebObject._Render%o<WebSource>%o<WebObject>i4
WebPage.Event_RenderHTML%o<WebSource>%o<WebPage>
WebView.Event_RenderHTML%o<WebSource>%o<WebView>
WebControl.Event_RenderHTML%o<WebSource>%o<WebControl>
WebObject._Render%o<WebSource>%o<WebObject>i4
WebSession._AddControl%%o<WebSession>o<WebControl>
Session.Session.frmUpdateInfo%o<frmUpdateInfo.frmUpdateInfo>%o<Session.Session>
App.DefaultPage%o<WebPage>%o<App>
WebSession._ExecuteEvent%%o<WebSession>sA1v&b
WebSession._HandleEvent%%o<WebSession>so<_HTTPServer.HTTPRequestContext>
WebSession._HandleRequest%i4%o<WebSession>so<_HTTPServer.HTTPRequestContext>
WebApplication._HandleHTTPRequest%%o<WebApplication>o<_HTTPServer.HTTPRequestContext>
_CGIGateway.GatewayRequestThread.Event_Run%%o<_CGIGateway.GatewayRequestThread>