Trouble coming back to pogo plug

[noobcakes]

I have a pogo v4 that has been sitting on a shelf for some time, turned off. Work has been mad, and even on weekends I haven't had time to mess with it. I turned it on today and attempted to update, only to find 404 errors for my mirror. That was easy enough to fix - just looked up the new mirror online and updated in /etc/pacman.d/mirrorlist

However, now I'm getting a different problem. When I try to sync pacman, I'm getting "missing required signature" errors on everything. My brain is all lazy from not having tinkered with it recently, so I really have no idea how to go about solving this.

Since there's nothing on it that would be drastically damaged by wiping clean, would it be better just to reset to factory default and then install arch again?

$this->bbcode_second_pass_code('', '[root@pogo ~]# pacman -Syu
:: Synchronizing package databases...
core 44.2 KiB 836K/s 00:00 [######################] 100%
extra 501.5 KiB 1693K/s 00:00 [######################] 100%
community 524.0 KiB 2.18M/s 00:00 [######################] 100%
alarm 6.0 KiB 3.89M/s 00:00 [######################] 100%
aur 17.0 KiB 3.84M/s 00:00 [######################] 100%
:: Starting full system upgrade...
:: Replace nss-myhostname with core/systemd? [Y/n] y
resolving dependencies...
looking for inter-conflicts...

Targets (92): acl-2.2.51-3 bash-4.2.045-1 binutils-2.23.1-3
ca-certificates-20130119-1 coreutils-8.21-1 cracklib-2.8.22-1
cryptsetup-1.6.1-1 curl-7.30.0-1 dash-0.5.7-3 dbus-1.6.10-1
device-mapper-2.02.98-3 diffutils-3.3-1 dirmngr-1.1.1-1
dnssec-anchors-20130320-1 e2fsprogs-1.42.7-1 expat-2.1.0-2
file-5.14-1 filesystem-2013.03-2 findutils-4.4.2-5
gcc-libs-4.7.2-4 gettext-0.18.2.1-1 glib2-2.36.1-3
glibc-2.17-3 gmp-5.1.1-1 gnupg-2.0.19-7 gpgme-1.4.1-1
grep-2.14-2 groff-1.22.2-2 gzip-1.5-3 hwids-20130228-1
iproute2-3.9.0-1 iptables-1.4.18-1 iputils-20121221-1
kbd-1.15.5-3 kmod-13-1 krb5-1.11.2-1 less-458-1
libarchive-3.1.2-1 libassuan-2.1.0-1 libcap-2.22-4
libffi-3.0.13-1 libgcrypt-1.5.2-1 libgpg-error-1.11-1
libidn-1.26-1 libksba-1.3.0-1 libldap-2.4.35-2 libnl-3.2.21-1
libpcap-1.3.0-3 libpipeline-1.2.3-1 libsasl-2.1.23-10
libtirpc-0.2.3-1 libusbx-1.0.15-1 licenses-20130203-1
lighttpd-1.4.32-4 linux-3.1.10-19 linux-api-headers-3.8.4-1
linux-firmware-20130430-1 linux-headers-3.1.10-19
logrotate-3.8.4-1 lvm2-2.02.98-3 lzo2-2.06-1 man-pages-3.51-1
mdadm-3.2.6-3 mkinitcpio-0.14.0-1 ncurses-5.9-5
nss-myhostname-0.3-3 [removal] ntfs-3g-2013.1.13-2
openssh-6.2p1-1 openssl-1.0.1.e-3 pacman-4.1.1-1
pacman-mirrorlist-20130424-1 pam-1.1.6-3 pambase-20130113-1
pciutils-3.2.0-2 perl-5.16.3-3 pinentry-0.8.3-1
procps-ng-3.3.7-1 psmisc-22.20-1 reiserfsprogs-3.6.22-1
sed-4.2.2-2 shadow-4.1.5.1-5 sqlite-3.7.16.2-1
syslog-ng-3.4.1-2 systemd-203-2 systemd-sysvcompat-203-2
tar-1.26-3 texinfo-5.1-1 tzdata-2013c-1 util-linux-2.23-1
which-2.20-6 xfsprogs-3.1.10-1 zlib-1.2.8-1

Total Installed Size: 378.87 MiB
Net Upgrade Size: -21.65 MiB

Proceed with installation? [Y/n] y
(91/91) checking package integrity [######################] 100%
error: acl: missing required signature
error: linux-api-headers: missing required signature
error: tzdata: missing required signature
error: filesystem: missing required signature
error: glibc: missing required signature
error: bash: missing required signature
error: zlib: missing required signature
error: binutils: missing required signature
error: cracklib: missing required signature
error: libtirpc: missing required signature
error: pambase: missing required signature
error: pam: missing required signature
error: gcc-libs: missing required signature
error: gmp: missing required signature
error: libcap: missing required signature
error: coreutils: missing required signature
error: perl: missing required signature
error: openssl: missing required signature
error: findutils: missing required signature
error: sed: missing required signature
error: ca-certificates: missing required signature
error: libgpg-error: missing required signature
error: libgcrypt: missing required signature
error: shadow: missing required signature
error: util-linux: missing required signature
error: expat: missing required signature
error: dbus: missing required signature
error: libffi: missing required signature
error: glib2: missing required signature
error: kbd: missing required signature
error: kmod: missing required signature
error: hwids: missing required signature
error: systemd: missing required signature
error: device-mapper: missing required signature
error: cryptsetup: missing required signature
error: curl: missing required signature
error: dash: missing required signature
error: diffutils: missing required signature
error: libsasl: missing required signature
error: e2fsprogs: missing required signature
error: libldap: missing required signature
error: libksba: missing required signature
error: libassuan: missing required signature
error: dirmngr: missing required signature
error: dnssec-anchors: missing required signature
error: file: missing required signature
error: gettext: missing required signature
error: ncurses: missing required signature
error: pinentry: missing required signature
error: gnupg: missing required signature
error: gpgme: missing required signature
error: grep: missing required signature
error: groff: missing required signature
error: gzip: missing required signature
error: iptables: missing required signature
error: iproute2: missing required signature
error: iputils: missing required signature
error: krb5: missing required signature
error: less: missing required signature
error: lzo2: missing required signature
error: libarchive: missing required signature
error: texinfo: missing required signature
error: libnl: missing required signature
error: libusbx: missing required signature
error: libpcap: missing required signature
error: libpipeline: missing required signature
error: licenses: missing required signature
error: linux-firmware: missing required signature
error: mkinitcpio: missing required signature
error: linux: missing required signature
error: linux-headers: missing required signature
error: logrotate: missing required signature
error: lvm2: missing required signature
error: man-pages: missing required signature
error: mdadm: missing required signature
error: openssh: missing required signature
error: pacman-mirrorlist: missing required signature
error: pacman: missing required signature
error: pciutils: missing required signature
error: procps-ng: missing required signature
error: psmisc: missing required signature
error: reiserfsprogs: missing required signature
error: systemd-sysvcompat: missing required signature
error: tar: missing required signature
error: which: missing required signature
error: xfsprogs: missing required signature
error: failed to commit transaction (invalid or corrupted package (PGP signature))
Errors occurred, no packages were upgraded.
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