Unrecoverable runtime E009

Hi, I wanted to try to generate some tests with Diffblue but unfortunately, I got this error.

Unrecoverable runtime error: Please contact Diffblue support. See https://diff.blue/E009

OS: Windows 10
Java: 11
Project Type: Java SE
Project dependencies:

<!--Network Management-->
<!-- Google GSON -->
<!-- Google Guava -->
<!-- JLine -->
<!-- Mockito -->
<!-- JUnit -->

I someone has any ideas. I will appreciate them.

1 Like

Hi @Horizon,

Thanks for getting in touch - and thanks for the detailed report, this is useful. I am sorry that we are not producing tests for you.

Are you able to attach the Diffblue Cover log file please? And if this is an open-source project it would be helpful for us to see the code, but I understand if that is not possible.

We will do everything we can to get this resolved for you



Thanks for your reply. Here is a log: https://pastebin.com/AJYwEz56

Unfortunately, project is not ready for open-source release so here is the code for a class that I want to generate:

import com.github.horizontier.data.Registry;
import com.github.horizontier.session.NetworkSession;

public class SessionRegistry extends Registry<NetworkSession, Boolean> {

public SessionRegistry() {

public void tick() {

public void add(NetworkSession session) {
super.add(session, true);

public void remove(NetworkSession session) {

Also, I noticed there is the behavior of these problems for example if I want to generate tests for a basic class that is using only basic things like Strings, Integers, etc, and is not extended or does not have any implementations. Tests are generated successfully. But if I want to generate tests for a class that contains custom objects like NetworkSession or is extended or has some implementations it does not work.

Thanks for your quick reply, and thanks for the code snippet, this is really helpful

We will try and recreate the scenario and get back to you :+1:

Thanks again


Hi @Horizon,
can you please post the log file again? The link above doesn’t work anymore.
Many thanks,

Yeah sure here: https://pastebin.com/AU8L34SH

Hi @Horizon - it still says “Pending moderation”? 403

I don’t know what is wrong with Pastebin. Anyway here is a file with it. Sorry for problems with it.


Thanks, @Horizon, I think we understand now what is going on.
There will be a fix in the next release 2021.05.2 expected for 25 May.
Please try that version then and let us know whether it fixed your problem.

@Horizon, was the problem fixed in 2021.05.2?

Sorry for the late response. But yes my problem was fixed. Thanks.