Some further investigation took me to the fact that over the years a multitude of openSSL file versions have accumulated on my system. Every application that comes bundled with some version of openSSL stores the relevant dlls in their own location.
To clean up the mess I downloaded the most recent version of openSSL and read some of the docs, which is obviously always a good idea if something seems to go wrong
.
In the end I managed to eliminate both the errors with Calibre's metadata download facility and wget complaining about not being able to check certificate validity by pointing openSSL via its environment variables
- OPENSSL_CONF
- SSL_CERT_FILE
to
The certificate collection is necessary because openSSL does
not use the Windows certificate store.