Send to Unreal A socket operation was attempted on an unreachable host

[Cesio137]

In the description paste in and edit the following:

• Addon: i.e Send to Unreal
• Steps to Reproduce the Problem: i.e. after updating the addon to version 1.4.10 this error started to appear. I just add any mesh to the Mesh collection and click export, but it doesn't work.
• Error Log:

Traceback (most recent call last):
File "C:\Users\natha\AppData\Roaming\Blender Foundation\Blender\2.90\scripts\addons\send2ue\operators.py", line 15, in execute
export.send2ue(properties)
File "C:\Users\natha\AppData\Roaming\Blender Foundation\Blender\2.90\scripts\addons\send2ue\functions\export.py", line 899, in send2ue
result = unreal.import_asset(assets_data, properties)
File "C:\Users\natha\AppData\Roaming\Blender Foundation\Blender\2.90\scripts\addons\send2ue\functions\unreal.py", line 54, in import_asset
remote_exec.start()
File "C:\Users\natha\AppData\Roaming\Blender Foundation\Blender\2.90\scripts\addons\send2ue\dependencies\remote_execution.py", line 81, in start
self._broadcast_connection.open()
File "C:\Users\natha\AppData\Roaming\Blender Foundation\Blender\2.90\scripts\addons\send2ue\dependencies\remote_execution.py", line 253, in open
self._init_broadcast_socket()
File "C:\Users\natha\AppData\Roaming\Blender Foundation\Blender\2.90\scripts\addons\send2ue\dependencies\remote_execution.py", line 282, in _init_broadcast_socket
self._config.multicast_group_endpoint[0]) + _socket.inet_aton('0.0.0.0'))
OSError: [WinError 10065] A socket operation was attempted on an unreachable host

location: :-1

• OS: i.e.Windows
• Addon Version: i.e. Send to Unreal 1.4.10
• Blender Version: i.e. Blender 2.90.1
• Unreal Version: i.e. Unreal 4.25.4

[james-baber]

@Cesio137 can you toggle the "remote execution" option off and on in your Unreal Project and see if the issue persists? I cannot reproduce this on my end

[Cesio137]

@james-baber I had already activated this option in the first installation of the plugin. Unfortunately the error remains the same enabling python remote execution

[james-baber]

@Cesio137 I am curious if this is a consistently reproducible bug for you. Can you try Turning Unreal off and on, and your computer off and on?

Firewall and Antivirus are also a possibility, but the remote execution code hasn't change in at least 3 months, so I think the new release might be a coincidence
https://github.com/EpicGames/BlenderTools/blob/master/send2ue/addon/dependencies/remote_execution.py

https://help.globalscape.com/help/archive/cuteftp6/socket_errors_10060,_10061,_10064,_10065.htm

After trying those things and if the issue still persists let me know and we can see if we can reproduce.
What AV software do you have runnning?
How long had your unreal editor instance been sitting open, before this occurred?
Thanks

[Cesio137]

@james-baber
AV: Windows defender Only
2. when i was using 1.4.9 it worked fine until saturday, i went to install the valorant and update plugin to have a little fun there after that started giving the error. I didn't update engine, windows or anything
Unfortunately continues to give the error I followed all the steps written above

[james-baber]

@Cesio137 Does downgrading to 1.4.9 consistently solve the issue or does it happen there too? It is possible that another application or process is blocking the port that remote execution needs to communicate across.... Anyone else experiencing this?

[james-baber]

I have seen this same error 2 or 3 times during my whole time developing this, but never had a situation where I could reproduce the issue consistently. It would happen once and then Id run send to unreal a thousand times and would never see that WinError 10065 again

[Cesio137]

@james-baber I will test if version 4.24 works, the reason for the downgrade is that I was having a lot of problems with 4.25. Just wait a moment until I get home

[james-baber]

Ok let me know how that goes. I am on a
Windows 10
Send to Unreal 1.4.11
Blender 2.90
Unreal 4.25.3

And it works, and the docker image we test on is
Ubuntu 18
Send to Unreal 1.4.11
Blender 2.90
Unreal 4.25.3

And is working. I feel there has to be a third party that is effecting that socket connection on your machine.

[drichardson]

Just a few crazy ideas to throw out:

1. Valorant installs Vangaurd, a kernel mode anti cheat. Perhaps this can interfere with networking? Seems unlikely but it was at least coincidental that you had the problems after installing Valorant.

2. I was able to reproduce this problem if I disabled my network interface. The code binds on 0.0.0.0, which means any address, but I think it also means any IPv4 address (not sure if it can bind to an IPv6 address). Is there any chance you have a weird network configuration (IPv6 only, or disabled network interfaces?).

3. Can you run other programs that bind on the any address (0.0.0.0)? If you have python3 installed, you can run this and then open a web browser at http://localhost:8000 to check:

   python -m http.server --bind 0.0.0.0 --port 8000

[drichardson]

One other thing. Before you start UE4 Editor, run this from a PowerShell prompt:

 netstat -an|sls 6766

Then start your project (that has Remote Execution enabled with the multicast group endpoint presumably set to 239.0.0.1:6766) and run the command again.

The first time, you run netstat, nothing should show up. The second time you run it, you should see this:

UDP    0.0.0.0:6766           *:*

[Cesio137]

@drichardson thanks for the reply, the problem was in the network interface (hamachi), I just didn’t understand why this was happening only a while later and they were already installed on the computer for a long time.

@james-baber now its all ok

[james-baber]

@Cesio137 ok awesome glad to hear

[oniregoc]

Hello, almost same problem here...windows defender and firewall disable because I am using comodo (don't like windows spy)...so @drichardson I tryed to apply your recommendation but can't get any positive result: http://localhost:8000 bring "unable to connect" (python 3.7 installed)...where am i wrong ?

using cmd give me this (is it the right way/path ?)
C:\Users*****>python -m http.server --bind 0.0.0.0 --port 8000
'python' is not recognized as an internal or external command,
operable program or batch file.

[james-baber]

That is probably because python is not on your PATH. I would try this #152 (comment) in PowerShell to check if the port is blocked

[Macarmoni]

edit: I'm sorry for bumping this thread again, I was really having issues, but a restart somehow resolved the issue.. No idea how! This is a strange one, thank you for all the suggestions discussed here, they helped me out a lot.