Unable to install rosserial on Ubuntu 18.04, using ROS melodic

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i think have the same problem, did you solve it???? I'm using ROS melodic on ubuntu 18.04

I tried to install rosserial with:

sudo apt-get install ros-melodic-rosserial
sudo apt-get install ros-melodic-rosserial-arduino

i get the error:

Get:1 http://de.archive.ubuntu.com/ubuntu bionic/universe amd64 binutils-avr amd64 2.26.20160125+Atmel3.6.0-1 [1.475 kB]
Err:2 http://packages.ros.org/ros/ubuntu bionic/main amd64 ros-melodic-rosserial-msgs amd64 0.8.0-0bionic.20190318.181339
  404  Not Found [IP: 2600:3402:200:227::2 80]

@colidar: you're issue would appear to be due to (for some reason) Ubuntu trying to use the IPv6 address to reach packages.ros.org, and failing. @ashutosh007 describes a very different problem.

Please post your problem as a new question.