pacstrap command fails because keys "could not be looked up remotely"

[LEOcab]

I'm following this install guide:
https://github.com/sigboe/GPD-ArchISO/wiki/Encrypted-installation

When I get to the pacstrap command, it fails with multiple errors like this:
error: key "9D4C5AA15426DA0A" could not be looked up remotely

Any idea what's wrong?

edit: I tried working around this by setting all the repos to SigLevel = Never but then it complains about "Unrecognized archive format" for every .pkg.tar.zst file that it tries to open

[sigboe]

Hello, this is because the ISO image is so outdated it doesn't have the newest keys to download and install all other packages.
I do not suggest using this ISO image, I suggest using the regular one, I believe most things should work out of the box, just using the regular kernel, following the regular Arch Linux install guide.

You may consult https://github.com/sigboe/GPD-ArchISO/wiki/Install-official-ArchISO to view generally how I set up the installation when I had the GPD Pocket 1, but there are some things you should not, or cant do anymore. I think wifi may be supported, check the arch wiki how to connect to wifi using the live iso. I think you also don't need to rotate the screen, if you do, there is instructions how to do that in the previous link. I presume you will still want a bigger font. But if you SSH into the GPD Pocket 1 from another machine, while booted into the official arch-iso you don't really need to adjust the font, if you can enable ssh with small text on screen.

IMPORTANT: Skip the step that is called "Install some of the GPD packages", the official linux kernel should have all the patches from Hans G, and even more improvements, and work better, you should not add the extra repository, it hasn't been updated since 2017.

IMPORTANT: The section called "Configure Boot enviornment" is not correct, follow the arch wiki instead if you are unsure. The only useful thing from there currently is that if you want to increase the console font during early boot you may need to add the "consolefont" to the beginning of the HOOKS array in /etc/mkinitcpio.conf, I don't think you need to do more changes to that array than that.

Other than that, later in the step by step, you won't find the GPD-fan example file, you may want to look into if you need something like that at all, and you don't need to manually install cower to install an aur helper. cower is now in the official repos and will be installed automatically if you install pacaur or another aur helper that needs cower.

On a side note I think to fix the issue you have on the ISO you can update the archlinux-keyring package before running the pacstrap command. But I do not suggest using the image, it will set up a system that will not run the latest and best kernel, and may have other issues, I don't recall what that can be.