Whilst updating Virtualmin, you might get this error: Err:6 https://software.virtualmin.com/vm/6/gpl/apt virtualmin-focal InRelease The following signatures were invalid: EXPKEYSIG D9F9010760D62A6B Virtualmin, Inc. (Package signing key for Virtualmin 6) <security@virtualmin.com> Err:7 https://software.virtualmin.com/vm/6/gpl/apt virtualmin-universal InRelease The following signatures were invalid: EXPKEYSIG D9F9010760D62A6B Virtualmin, Inc. (Package signing key for Virtualmin 6) <security@virtualmin.com> Reading package lists… Done Do this: sudo … Continue reading Virtualmin doesn’t upgrade: How to fix invalid signature Virtualmin apt packages