Error while installing updates 3.0

[aus9]

I hope Jerry does not mind making some comments and suggestions?

open a terminal and convert to root by command sudo su
for me, after running apt-get update I see that I do not have the same issue as OP but am on a diff server list....showing above and below results to show no errors

Hit:10 http://archive.canonical.com xenial InRelease                                                                                                 
Hit:11 http://repo.linuxliteos.com/linuxlite citrine InRelease                                         
Hit:12 http://ppa.launchpad.net/nemh/systemback/ubuntu xenial InRelease

suggestion this is one way to fix the GPG errors for technomancer

copy and paste this into your root powered terminal and I show my result

#!/bin/sh
LIST="40976EAF437D05B5 3B4FE6ACC0B21F32  22AAEA0A86A02625 "
for Z in $LIST
    do
  gpg --recv-key $Z && gpg -a --export $Z | apt-key add -
done

Code:

# my result
root@asus:/home/gordon# #!/bin/sh
root@asus:/home/gordon# LIST="40976EAF437D05B5 3B4FE6ACC0B21F32  22AAEA0A86A02625 "
root@asus:/home/gordon# for Z in $LIST
>     do
>    gpg --recv-key $Z && gpg -a --export $Z | apt-key add -
> done
gpg: requesting key 437D05B5 from hkp server keys.gnupg.net
gpg: key 437D05B5: public key "Ubuntu Archive Automatic Signing Key <[email protected]>" imported
gpg: no ultimately trusted keys found
gpg: Total number processed: 1
gpg:               imported: 1
OK
gpg: requesting key C0B21F32 from hkp server keys.gnupg.net
gpg: key C0B21F32: public key "Ubuntu Archive Automatic Signing Key (2012) <[email protected]>" imported
gpg: no ultimately trusted keys found
gpg: Total number processed: 1
gpg:               imported: 1  (RSA: 1)
OK
gpg: requesting key 86A02625 from hkp server keys.gnupg.net
gpg: key 86A02625: "Jerry Bezencon (Linux Lite) <[email protected]>" not changed
gpg: Total number processed: 1
gpg:              unchanged: 1
OK
root@asus:/home/gordon#

thanks to technomancer......you then need to repeat the code and then
If you see 3 successful OKs then run as root command .......after doing the commands twice, run next command to finish the changes

Code:

apt-get update

and hopefully you have eliminated those gpg errors

###########################
Now back to OP

can you post the contents of /etc/apt/sources.list.d/linuxlite.list/linuxlite.lst

I show mine in case it helps on 3.0 64 bit

deb http://repo.linuxliteos.com/linuxlite/ citrine main

I wonder, and I am new to LL if there has been a mixup with an update from an earlier install of LL?
If Jerry says it OK, you could just update your file but Jerry may not like me....well who can blame him....heh heh

so another suggestion for OP is open a terminal and show the full output of

Code:

sudo apt-get update

in the hope it might show more issues due to wrong sources