With 1.950 IO::Socket::SSL switched the default from "no certificate verification" to "require verification", after 3 years of complaining (since 1.79) if you used the insecure default of no verification. It also uses the default location for the certificates provided by the openssl installation.

On windows there are probably no certificates installed in a form usable by openssl, so you have to do it by your own. You might use Mozilla::CA and then set the SSL_ca_file like documented there.