Answer by vinjana for Conda update fails with SSL error CERTIFICATE_VERIFY_FAILED

For me the problem was the proxy configuration. I had in my .condarc:

proxy_servers:    http: http://our.proxy.org:80/    https: https://our.proxy.org:80/

that did not work. Instead, the HTTPS proxy had to be specified with the http protocol (i.e. without the s). So,

proxy_servers:    http: http://our.proxy.org:80/    https: http://our.proxy.org:80/