I set up a year and a half ago and it all worked. What could I have misconfigured or duplicated?
Looks like the identity files got corrupted somehow. 2 nodes died.
This error indicating that you provided a wrong path to the identity folder during setup, this identity is not signed.
Did you generate a new one instead of using the old one? Because if so, your old node will be disqualified, and its data will be slowly moved to the trash folder by the garbage collector, because for a new identity this data is garbage, because it belongs to the old one.
Since you have multiple nodes, make sure that you did not confuse identities.
We usually recommend to copy the identity to the disk with data, and use this path instead of your home directory, because the identity without its data is useless and data without its identity is useless too, and also it could help to do not confuse them in the situation when you reinstall your setup.
This could be related to the corruption of your system disk, and likely you have your identities there. This also could explain, why the storagenode binary got corrupted too.
could be related to the system disk corruption as well, Windows GUI nodes uses the installation directory to store logs by default.