Unverified signatures

Support and Help
1

If I execute sudo apt update, I get the following:

Hit:1 http://ee.archive.ubuntu.com/ubuntu noble InRelease
Get:2 http://ee.archive.ubuntu.com/ubuntu noble-updates InRelease [126 kB]     
Hit:3 http://security.ubuntu.com/ubuntu noble-security InRelease               
Get:4 http://ee.archive.ubuntu.com/ubuntu noble-backports InRelease [126 kB]   
Get:5 http://ee.archive.ubuntu.com/ubuntu noble-proposed InRelease [265 kB]    
Hit:6 https://ppa.launchpadcontent.net/costales/anoise/ubuntu noble InRelease  
Hit:7 https://ppa.launchpadcontent.net/danielrichter2007/grub-customizer/ubuntu noble InRelease
Err:1 http://ee.archive.ubuntu.com/ubuntu noble InRelease                 
  The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 871920D1991BC93C
Hit:8 https://ppa.launchpadcontent.net/mozillateam/ppa/ubuntu jammy InRelease
Ign:9 https://ppa.launchpadcontent.net/webupd8team/y-ppa-manager/ubuntu noble InRelease
Err:10 https://ppa.launchpadcontent.net/webupd8team/y-ppa-manager/ubuntu noble Release
  404  Not Found [IP: 2620:2d:4000:1::81 443]
Hit:11 https://esm.ubuntu.com/apps/ubuntu noble-apps-security InRelease
Hit:12 https://esm.ubuntu.com/apps/ubuntu noble-apps-updates InRelease
Hit:13 https://esm.ubuntu.com/infra/ubuntu noble-infra-updates InRelease
Err:2 http://ee.archive.ubuntu.com/ubuntu noble-updates InRelease
  The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 871920D1991BC93C
Hit:14 https://esm.ubuntu.com/infra/ubuntu noble-infra-security InRelease
Err:4 http://ee.archive.ubuntu.com/ubuntu noble-backports InRelease
  The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 871920D1991BC93C
Err:5 http://ee.archive.ubuntu.com/ubuntu noble-proposed InRelease
  The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 871920D1991BC93C
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: http://ee.archive.ubuntu.com/ubuntu noble InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 871920D1991BC93C
E: The repository 'https://ppa.launchpadcontent.net/webupd8team/y-ppa-manager/ubuntu noble Release' does not have a Release file.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.
W: An error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error: http://ee.archive.ubuntu.com/ubuntu noble-updates InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 871920D1991BC93C
W: GPG error: http://ee.archive.ubuntu.com/ubuntu noble-backports InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 871920D1991BC93C
E: The repository 'http://ee.archive.ubuntu.com/ubuntu noble-backports InRelease' is not signed.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.
W: GPG error: http://ee.archive.ubuntu.com/ubuntu noble-proposed InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 871920D1991BC93C
E: The repository 'http://ee.archive.ubuntu.com/ubuntu noble-proposed InRelease' is not signed.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.

How to solve this mess? I am using the latest Ubuntu 24.04 LTS 64-bit.

2

https://ppa.launchpadcontent.net/webupd8team/y-ppa-manager/ubuntu/dists/
PPA doesn’t support noble, so should be removed. Not all PPAs support all releases of Ubuntu

2 Likes
3

https://askubuntu.com/questions/1459005/cant-add-a-public-key-to-ubuntu-22-04

Seems this is needed too

1 Like
4

If I followed the first suggestion there, I get the attached errors:
image

[�����lr��q%ظ�
              ��#l��[4���s�P����*upG
                                    �p�d�	 �D�<�D�8�eZ|�Q�Xv�Z���%��ww�P���|��L��Al
         �3�4���L�z-�N8-{]I1�މ�C���"�j_�Y����_A�����v��K�X|�藡�,Yk1{U~⎓}�vaTe^D/$(t,'��!���������T�B���
                       u�u�6���3Qy�E���VJ����
                                             mAm�9!z�7�)w��9-tPM�.��m��G�?#�P^�}H�#�Z/(&�s�$>#��B��Pڈ�����y�����
                                ��O��������jV\��ڍ�����B��K���Kۨs��`���6����:�JFho�Ch�
    ��t?ݕu��=�H��%���
�1�ŕN��BEV��a.���)ÔI�(g���'3��7��BUbuntu Archive Automatic Signing Key (2018) <ftpmaster@ubuntu.com>�8
"[���
     	


	� љ<,s��r|s����#�����mめ�Cm!
�Cee��n����@�,%�w'9v�<��̔����[��t�	��c�2pOe��Fh\��� {mda�[Λu-6~I��;z�i�4Zf_X�m롫`�q:U�qn�ܐ������r*)s���dƧ��`���SK�Z ���5��o�n38@�`ܱ��^�@m�%��Q��xy
�!�E��X�sϏb�N�X�$��htj���|d��ܤ��|���
������/4��-�L0�+/��
                   �܁
I(c,Y�_WQ
#����dJ�
o�o�c�P+ʸ\*pF���S�[��6Y�].��;���@y(R�X<�|)>+���jh�b��`[����)��*�#Ku �7N�A�5}F�@Ks�1��9�)&g��DO��1
��8��5�Ĉ��`{/K��J�
���r��^ۼQ�
��`��V�F2eE�Ǡ��w�#5�mz��b����^|�R\-	L�&�

Hit:1 http://ee.archive.ubuntu.com/ubuntu noble InRelease
Get:2 http://ee.archive.ubuntu.com/ubuntu noble-updates InRelease [126 kB]     
Hit:3 http://security.ubuntu.com/ubuntu noble-security InRelease               
Get:4 http://ee.archive.ubuntu.com/ubuntu noble-backports InRelease [126 kB]   
Get:5 http://ee.archive.ubuntu.com/ubuntu noble-proposed InRelease [265 kB]    
Hit:6 https://ppa.launchpadcontent.net/mozillateam/ppa/ubuntu jammy InRelease  
Err:1 http://ee.archive.ubuntu.com/ubuntu noble InRelease                      
  The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 871920D1991BC93C
Hit:7 https://esm.ubuntu.com/apps/ubuntu noble-apps-security InRelease
Err:2 http://ee.archive.ubuntu.com/ubuntu noble-updates InRelease
  The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 871920D1991BC93C
Hit:8 https://esm.ubuntu.com/apps/ubuntu noble-apps-updates InRelease
Hit:9 https://esm.ubuntu.com/infra/ubuntu noble-infra-updates InRelease
Hit:10 https://esm.ubuntu.com/infra/ubuntu noble-infra-security InRelease
Err:4 http://ee.archive.ubuntu.com/ubuntu noble-backports InRelease
  The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 871920D1991BC93C
Err:5 http://ee.archive.ubuntu.com/ubuntu noble-proposed InRelease
  The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 871920D1991BC93C
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: http://ee.archive.ubuntu.com/ubuntu noble InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 871920D1991BC93C
W: An error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error: http://ee.archive.ubuntu.com/ubuntu noble-updates InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 871920D1991BC93C
W: GPG error: http://ee.archive.ubuntu.com/ubuntu noble-backports InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 871920D1991BC93C
E: The repository 'http://ee.archive.ubuntu.com/ubuntu noble-backports InRelease' is not signed.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.
W: GPG error: http://ee.archive.ubuntu.com/ubuntu noble-proposed InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 871920D1991BC93C
E: The repository 'http://ee.archive.ubuntu.com/ubuntu noble-proposed InRelease' is not signed.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.
5

Could try:

sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys 871920D1991BC93C

6

I got: Warning: apt-key is deprecated. Manage keyring files in trusted.gpg.d instead (see apt-key(8)). Executing: /tmp/apt-key-gpghome.vT8bvNrk7b/gpg.1.sh --keyserver keyserver.ubuntu.com --recv-keys 871920D1991BC93C gpg: key 871920D1991BC93C: "Ubuntu Archive Automatic Signing Key (2018) <ftpmaster@ubuntu.com>" not changed

7

https://itsfoss.com/apt-key-deprecated/

You’ll need to add the key using the new way then

8

I did this: sudo apt-key export 991BC93C | sudo gpg --dearmour -o /etc/apt/trusted.gpg.d/ubuntu-keyring-2018-archive.gpg and I got
File '/etc/apt/trusted.gpg.d/ubuntu-keyring-2018-archive.gpg' exists. Overwrite? (y/N) Warning: apt-key is deprecated. Manage keyring files in trusted.gpg.d instead (see apt-key(8)). y
I did correctly?