[SOLVED] PVE Upgrade 8 to 9 - Conflicting values set for option Signed-By

[Nighthawkinlight]

Ok that makes sense.
Please remove all files in the sources.list.d directory and run the following:

cat > /etc/apt/sources.list.d/proxmox.sources << EOF
Types: deb
URIs: http://download.proxmox.com/debian/pve
Suites: trixie
Components: pve-no-subscription
Signed-By: /usr/share/keyrings/proxmox-archive-keyring.gpg
EOF

cat > /etc/apt/sources.list.d/ceph.sources << EOF
Types: deb
URIs: http://download.proxmox.com/debian/ceph-squid
Suites: trixie
Components: no-subscription
Signed-By: /usr/share/keyrings/proxmox-archive-keyring.gpg
EOF

cat > /etc/apt/sources.list.d/debian.sources << EOF
Types: deb                                                                                                                                                
URIs: http://deb.debian.org/debian/                                                                                                                                
Suites: trixie trixie-updates                                                                                                                                      
Components: main contrib non-free-firmware                                                                                                                        
Signed-By: /usr/share/keyrings/debian-archive-keyring.gpg                                                                                                          
                                                                                                                                                                   
Types: deb                                                                                                                                                
URIs: http://security.debian.org/debian-security/                                                                                                                  
Suites: trixie-security                                                                                                                                            
Components: main contrib non-free-firmware                                                                                                                        
Signed-By: /usr/share/keyrings/debian-archive-keyring.gpg
EOF

Then run apt clean && apt update

This should configure the proper Proxmox and Debian sources.

You’ve saved another upgrade. I was stuck on the same issue OP had above and this right here fixed everything. Just wanted to make sure you knew. Thanks!