sudo apt-get update issue & error

Question

May I know how to repair the corrupted files?

pi@raspberrypi:~ $ sudo apt-get update
Get:1 http://mirrordirector.raspbian.org jessie InRelease [1,733 B]
100% [1 InRelease gpgv 1,733 B] [Waiting for headers]Splitting up /var/lib/apt/lists/partial/mirrordirector.raspbian.org_raspbian_dists_jessie_InRelease into daErr http: // mirrordirector.raspbian.org jessie InRelease

Get:2 http:// archive.raspberrypi.org jessie InRelease [1,733 B]
100% [2 InRelease gpgv 1,733 B]Splitting up /var/lib/apt/lists/partial/archive.rErr http://archive.raspberrypi.org jessie InReleaseata and signature failed

Fetched 3,466 B in 0s (6,080 B/s)
Reading package lists... Done
W: An error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error:  mirrordirector.raspbian org jessie InRelease: Clearsigned file isn't valid, got 'NODATA' (does the network require authentication?)

W: An error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error:   archive.raspberrypi org jessie InRelease: Clearsigned file isn't valid, got 'NODATA' (does the network require authentication?)

W: Failed to fetch mirrordirector raspbian org/rasp ... / InRelease 

W: Failed to fetch archive.raspberrypi org/debian/d ... / InRelease 

W: Some index files failed to download. They have been ignored, or old ones used instead.

Answer 1

I think you are using Wi-Fi to upgrade. Try with an Ethernet connection. Also try the follow command:

sudo apt-get upgrade --fix missing

Answer 2

You might have have to upgrade your Pi.

sudo apt-get upgrade

Then upgrade the distribution using:

sudo apt-get dist-upgrade

Then reboot:

sudo reboot

Answer 3

You have to Upgrade:

sudo apt upgrade

After Upgrading, run these commands:

sudo apt-get upgrade --fix-missing
sudo dpkg --configure -a

Reboot your RPi and try to update again.