It seems I'm unable to upgrade installed packages with Guix. Below is the output from the terminal. As you see I first tried to get the latest Guix before upgrading. Is this an necessary step? In any case, it was unsuccessful too. I don't believe I've ever been able to upgrade packages. I've only trieda few times from memory. Before today I did try the --fallback option as the error messages suggest but it seemed to be downloading many files and as I was unsure what it was actually doing I abandoned it. *[13:15 doolio@mars ~] > guix pullStarting download of /tmp/guix-file.BxhQnXFrom https://git.savannah.gnu.org/cgit/guix.git/snapshot/master.tar.gz. .. ….tar.gz 1.1MiB/s 00:12 | 13.0MiB transferredunpacking '/gnu/store/7cs79c2d12cdxzam904f8nldidxhmns6-guix-latest.tar.gz'...substitute: updating list of substitutes from 'https://mirror.hydra.gnu.org '... 100.0%The following derivations will be built: /gnu/store/szq1skj2r10nnlpwhhybz5a5s7xaqjds-guix-latest.drv /gnu/store/7lla86k1270v3hwmn0cill79lm9v5rr3-module-import.drv /gnu/store/slclx1brrfw4c0icgx6dw3c8ssf35b7w-module-import-compiled.drvThe following files will be downloaded: /gnu/store/49lfsdrai7w2bl7hip7p7qamm2fqv6sf-xz-5.2.2 /gnu/store/b17aiw216bqzdk33d3mmdlcw4cydsa4q-bzip2-1.0.6fetching path `/gnu/store/b17aiw216bqzdk33d3mmdlcw4cydsa4q-bzip2-1.0.6'...Downloading https://mirror.hydra.gnu.org/guix/nar/gzip/b17aiw216bqzdk33d3mmdlcw4cydsa4q-bzip2-1.0.6 (547KiB installed)...guix substitute: error: download from 'https://mirror.hydra.gnu.org/guix/nar/gzip/b17aiw216bqzdk33d3mmdlcw4cydsa4q-bzip2-1.0.6 ' failed: 404, "Not Found"fetching path `/gnu/store/b17aiw216bqzdk33d3mmdlcw4cydsa4q-bzip2-1.0.6' failed with exit code 1fetching path `/gnu/store/49lfsdrai7w2bl7hip7p7qamm2fqv6sf-xz-5.2.2'...killing process 2773guix pull: error: build failed: some substitutes for the outputs of derivation `/gnu/store/ml3xbmccnjvm3lx0mlay4jybqncj2zis-bzip2-1.0.6.drv' failed (usually happens due to networking issues); try `--fallback' to build derivation from source [13:19 doolio@mars ~] > guix package -usubstitute: updating list of substitutes from 'https://mirror.hydra.gnu.org '... 100.0%substitute: updating list of substitutes from 'https://mirror.hydra.gnu.org '... 100.0%substitute: updating list of substitutes from 'https://mirror.hydra.gnu.org '... 100.0%substitute: updating list of substitutes from 'https://mirror.hydra.gnu.org '... 100.0%substitute: updating list of substitutes from 'https://mirror.hydra.gnu.org '... 100.0%substitute: updating list of substitutes from 'https://mirror.hydra.gnu.org '... 100.0%substitute: updating list of substitutes from 'https://mirror.hydra.gnu.org '... 100.0%substitute: updating list of substitutes from 'https://mirror.hydra.gnu.org '... 100.0%substitute: updating list of substitutes from 'https://mirror.hydra.gnu.org '... 100.0%substitute: updating list of substitutes from 'https://mirror.hydra.gnu.org '... 100.0%Downloading https://mirror.hydra.gnu.org/guix/nar/d6y1yklydd0xjhfil47sb0mr65akcmkm-emacs-guix-0.3.tar.gz (335KiB installed)... emacs-guix-0.3.tar.gz 335KiB 1.1MiB/s 00:00 [####################] 100.0%Downloading https://mirror.hydra.gnu.org/guix/nar/gzip/ff48qqv6vgizf3fv1h01ajl14l97wjlz-binutils-2.27 (42.1MiB installed)...guix substitute: error: download from 'https://mirror.hydra.gnu.org/guix/nar/gzip/ff48qqv6vgizf3fv1h01ajl14l97wjlz-binutils-2.27 ' failed: 404, "Not Found"killing process 2806guix package: error: build failed: some substitutes for the outputs of derivation `/gnu/store/dkpnh0ivzw9r5pb5ghprlf33ppjlyx02-binutils-2.27.drv' failed (usually happens due to networking issues); try `--fallback' to build derivation from source* Thanks for Guix and your time, Niall (irc doolio)