You saved me a lot of time.
Still on testnet. Had system issues with Ubuntu, so I reinstalled Ubuntu 20.04 LTS.
Then tried to install latest release of cardano-node 1.19.1 on testnet which doesn’t work out of the box - has issue finding cardano-node binary and correct path to the binary. I don’t even know if it installed the binary - I couldn’t find it.
Downgraded to 1.19.0 testnet, then half way through entire stake-pool course, I come across this same issue, but in manifests itself in a different form in that it won’t allow you to generate vrf keys.
I figured out to add the extra package libsodium-dev from some other post on this forum, then recompiled and re-installed libsodium binary (don’t know if this step was necessary), but I didn’t know to “re-export” LD_LIBRARY_PATH. I thought exporting paths was a one-time deal. I guess it’s a form of updating to the system what newly added or modified libraries are available in LD_LIBRARY_PATH.
Had I not come across your post, I would have downgraded to 1.18.0 and started over.