I'm trying to use Intel Graphics Installer, but i get the following error:
E:GPG error: http://ppa.launchpad.net trusty InRelease: Clearsigned file isn't valid, got 'NODATA' (does the network require authentication?)
I've searched through the internet, but none of the answers i found helped me to solve this issue.
Also, using the command
sudo apt-get update
I get a similar error at the end, sometimes accusing different ppa's. What should i do?