Epic launcher and UEngine cause internet bug


I have a very strange bug, when I launch the epic launcher or the engine, my internet connection become and remain very slow.

I can’t navigate to the internet, so I have investigate:
- It doesn’t depend of the browser (same issue with chrome and firefox)
- It seems only a download speed problem ( I 've tried using teamspeak, other people can ear me, but I ear them intermittently, if I close the launcher and the engine, it become normal again)
- This bug append if i start only the launcher or only the engine
- No problem with hardware (Cpu ~ 7%, Ram 4/ 16Go, Gpu 980GTX)
- Driver up to date, windows too.

I have tried adding the “-debugging” argument to the launcher, I don’t understand the log:

Download log file

Thanks for your help,
King Regards


I’m sorry to hear that you are having trouble. It appears that you may be downloading a file when the launcher is open. Can you please check your available tabs to see if any of your Epic client software is updating. This could include versions of the Unreal Engine, Shadow Complex, Fortnite (if you have access), and Paragon (if you have access).

Thanks for your reply,

The launcher is very slow to start (probably because of this downloading problem). I will try to start it this night, and let it download all the night.
We will see tomorrow if the problem remains.
I have found a way to bypass this problem, if I launch unreal engine with the visual studio debugger it works fine.

I keep you posted later.

I have checked the available tabs, and it appears that i am not downloading nothing.
I also downloaded NetBalancer, it is a software to monitor and rules the bandwidth of any software in your computer.
The launcher is continually downloading at 92 B/s , which is very few.
What I don’t understand is why this cause me some internet trouble, I have tried to monitor what happen, I have downloaded a big file, started the launcher, and my downloading speed suddenly has reduced from 1.5MB/s to 150KB/s and became unstable, with sometimes real cut (and the download failed).
I am not a specialist, but maybe the launcher is loop requesting something to your server, with a bad request, which make me thought that maybe (this is just a supposition) it could be a ssl problem? (windows failed to authenticate the ssl connection and cut it, or something like that…).

Waiting for your answer, I have put the bandwidth of the launcher very low, and it seems to work.

I’m sorry that we weren’t able to follow up with you promptly. We have recently changed our process for providing Launcher support, so if you are still experiencing this issue with the Launcher please visit http://help.epicgames.com/ for technical support, here you can find information and solutions for common issues, as well as a contact form if you still need additional assistance. Thanks!

I have the exact same problem. Huge packet loss, ping peaks, timeout.
It occur everytime with epic games launcher or product.

This is not a problem related to my internet connection. For the simple reason that I have 1gbps on download, 250mbps on upload.