When I do a ‘dnf update’ I get the following message:

Package skypeforlinux_8.62.0.83-1.x86_64.rpm is not signed
The downloaded packages were saved in cache until the next successful transaction.
You can remove cached packages by executing ‘dnf clean packages’.
Error: GPG check FAILED

It won’t update anything until I resolve this, but I have no idea how to do so. I don’t understand why it won’t install anything because there’s a problem with one package.

[Update a while later]

OK, new mystery. I want to set up Windows as a virtual machine, so I hooked up an SSD to put it on. But when I do so, I don’t see anything in the file manager. What’s even weirder is that when I look at /dev, all I see is sdb and sdb1, with no sda. But I know that my OS is on an SSD (presumably sda1), and /home is on a separate hard drive (which would be sdb1). How is this machine even running?

[Update a few minutes later]

OK, I’ve tried two different SSDs with two different cables, but I am not getting an sdc. I shouldn’t have to reboot, should I?

[Update a few more minutes later]

Never mind, bad power connector. But I still don’t understand why I’m not seeing my boot/root drive as sda.

[Update a while later]

OK, I rebooted, and now I see all the drives.