GPG error in apt-get update

Question

Few minutes ago I ran the following command and it worked fine as always:

sudo apt update
sudo apt upgrade

Then after about 10 minutes, I ran the same command again:

sudo apt-get update

Ign http: //fi.archive.ubuntu.com trusty InRelease
Get:1 http://fi.archive.ubuntu.com trusty-updates InRelease [64.4 kB] 
Ign http: //dl.google.com stable InRelease     
Get:2 http://fi.archive.ubuntu.com trusty-backports InRelease [64.5 kB]        
Ign http: //fi.archive.ubuntu.com trusty-updates InRelease                      
E: GPG error: http: //fi.archive.ubuntu.com trusty-updates InRelease:
The following signatures were invalid: NODATA 2

I tried reading every post in askubuntu and stackoverflow and so far nothing. The following is the only thing that sound rational to me and it didn't solve the issue:

sudo mv lists lists.old
sudo mkdir -p lists/partial
sudo apt-get clean
sudo apt-get update

any suggestions in appreciated.

UPDATE: even my Thunderbird was crashing immediately after loading, so I rebooted the computer and I ran the apt-get update again and I got:

sudo apt update
.
.
.
Fetched 32.2 MB in 10s (3,044kB/s)                                            
Reading package lists... Done
W: GPG error: http://ftp.sunet.se trusty/ Release: The following signatures were invalid: KEYEXPIRED 1445181253 KEYEXPIRED 1445181253 KEYEXPIRED 1445181253

Can you increase logging to see which files it fetches, and whether those files actually exist on the server you are downloading from? — tripleee, Nov 30 '15 at 09:44
first, try a different server like archive.ubuntu.com instead — mchid, Nov 30 '15 at 09:50
@tripleee your comment is valid but before I get the chance to read it, I rebooted the computer and situation changed, logging would not be helpful at this point. (I updated the post accordingly) — Mehrad Mahmoudian, Nov 30 '15 at 09:54
@davidbaumann date and time were correct at the time of this incident. — Mehrad Mahmoudian, Nov 30 '15 at 13:09

score 7 · Accepted Answer · edited Jun 12 '20 at 14:37

What I did to solve my question after rebooting and googling more:

reboot (Reboot the computer)
sudo apt-get update (this will give you a warning about expired keys)
apt-key list | grep expired (as suggested in another post) and I got:

pub 2048R/E084DAB9 2010-10-19 [expired: 2015-10-18]
copy the key ID is the bit after the / (in my case E084DAB9)
sudo apt-key adv --recv-keys --keyserver keys.gnupg.net E084DAB9 (remember to change the key ID of this command to the one you get from your computer)
sudo apt update
sudo apt upgrade

GPG error in apt-get update

1 Answers1